Camera sensors are designed to mimic the way the human eye/brain system perceives a portion of the electromagnetic spectrum as light. Our brains create the perception of color when stimulated by various wavelengths of the electromagnetic spectrum that we call "visible light". There are no colors intrinsic to any wavelength in the electromagnetic spectrum, there are only colors created by the perception of certain wavelengths by vision systems. What the human eye perceives as "blue" may not be perceivable at all by an insect. That same insect, however, can perceive infrared wavelengths that human eyes can't see at all.
There's no fundamental difference between other wavelengths in the electromagnetic spectrum and what we call "visible light" except the fact that our retinas react biologically to the wavelengths we refer to as visible light and do not react in the same way to other wavelengths of electromagnetic radiation. In other words, we call it visible light because properties of our vision system cause a biological reaction to those certain wavelengths, not because any unique properties of those wavelengths make them visible. X-rays, ultraviolet, infrared, etc. are all fundamentally the same as visible light, but our eyes do not react to those wavelengths.
The degree of the responses of each of the the three types of cones in the human retina depend on the specific wavelength(s) included in the light falling on the retinal cones. Our S-cones ("S" is for short wavelengths) have a higher response to shorter wavelengths of visible light, our L-cones ("L" is for long wavelengths) have a higher response to longer wavelengths of visible light, and our M-cones ("M" is for medium wavelengths) have a higher response to medium wavelengths of visible light. But all three types of cones have some reaction to a wide range of the visible spectrum. There's a LOT of overlap between the response of our "red" cones (which are actually most sensitive to lime-green light) and our "green" cones (which are actually most sensitive to a slightly yellow shade of green light). There's also some overlap between the "red" and "green" cones and the "blue" cones (which are most sensitive to light that is somewhere between blue and violet).
The sensitivities of the three types of human retinal cones with the response curve for each type of cone drawn in the color that we perceive for each of the wavelengths to which each, respectively, is most sensitive:
We didn't actually nail down the exact sensitivity curves for each type of retinal cone until the 1990s, long after we had discovered that we could create the perception of a wide variety of colors by mixing red, green, and blue light in various proportions (or also by mixing cyan, yellow, and magenta ink in various proportions on reflective surfaces such as paper).
Our camera sensors usually have a color filter array in front of them that mimic the different sensitivities to various wavelengths of light that our retinal cones demonstrate.
As you can see from the illustration, there's less overlap between the "green" and "red" filters than there is between our M (medium wavelength) cones and L (long wavelength) cones, but there's still plenty of overlap. You can also see that there is no singular wavelength of light that can pass through the "green" filter that won't also pass through the "red" and "blue" filters at a lower attenuation.
There's no hard cutoff between the filter colors, such as with a filter used on a scientific instrument that only lets a very narrow band of wavelengths through. It's more like the color filters we use on B&W film. If we use a red filter with B&W film all of the green objects don't disappear or look totally black, as they would with a hard cutoff. Rather, the green objects will look a darker shade of grey than red objects that are similarly bright in the actual scene.
We may call the three colors of the filter array "red", "green", and "blue", but those aren't the actual colors used in the CFAs of our digital cameras, all of the cute little RGB checkerboards plastered all over the internet notwithstanding.
(Note: Our emissive displays, however, do attempt to emit colors very close to the "red", "green", and "blue" used in those 'RGB' checkerboards. Thus the "red", "green", and "blue" filters in our digital cameras' filter arrays are not the same three colors as the "red", "green", and "blue" light emitted by our RGB display devices! Nor are they the "cyan", "magenta", and "yellow" used by our subtractive color printing systems.)
Though the exact shades used varies from one sensor design to the next, they all actually use similar shades of violet-blue, a slightly yellow shade of green, and a shade that is somewhere between yellow and orange. This last color seems to be the one that can vary the most from one sensor design to another.
Below is a microscopic view of a sensor that has had part of the color filter array scrapped off. Notice the colors of the filter array are not what we usually mean when we say "red", "green", and "blue".
In summary, here's the conclusion from this answer to Why do pure colors (red/green/blue) become a mixture of colors when converting raw?
For a camera to create "pure" colors when pointed at an RGB display, one would need a sensor that has a "red" channel that does not respond at all to Green or Blue light emitted by the RGB display, a "green channel" that does not respond at all to Red or Blue light, and a "blue" channel that does not respond at all to Green or Red light. But such a camera would not be able to construct any colors other than pure Red, pure Green, and pure Blue. There would be no way to synthesize other colors using overlapping sensitivities of "red", "green" and "blue" filtered photosites that mimic the way our retinal cones and our brains combine to synthesize colors based on the overlapping sensitivities of our S, L, and M cones.
Related questions/answers here at Photography SE for further reading:
How can a camera pick up and process colors?
Why don't mainstream sensors use CYM filters instead of RGB?
What would happen if a camera used entirely different primary colors?
How does a modern digital camera process to jpg?
Why is it that when the green channel clips, it turns into blue?
Why are Red, Green, and Blue the primary colors of light?
For a rather lengthy explanation of how we use RGB emissive displays to recreate perceptions of various colors in the human eye/brain system, please see this answer to a tangentially related question. The answer draws quite a bit from this color theory tutorial hosted on Memcode.