I thought that these two names were synonymous, but for example, the same manufacturer has both a product described as a monolight and one described as a studio strobe available with approximately the same specs and features, and at the same price point.
Is there a meaningful difference between monolight and studio strobe, or is this just an example of a couple of product lines overlapping?
There's no difference nor specific meaning in the usage of the terms. These are basically the same thing. Like saying car or automobile, same meaning. However, to me, the term Strobe means a very rapidly flashing continuing light (like seen in some dance halls), which these are NOT. And Flash means a single flash for photography, which these ARE, but some people do imagine any flash is also called strobe.
Monolight just means the power supply is built into the individual flash unit, a standalone unit offering greater control. Old time studio lights often shared a common power supply and battery using power cables. Technology makes change possible.
The actual distinction for flash mode is Speedlight, which is typically all camera mounted flash, however some few newer studio lights are adapting that principle now. A studio flash typically controls low power with lower flash tube voltage, and therefore lower power is slower (longer) speed duration. But Speedlights are always recycled to full power, but they control power by abruptly cutting it off for low power levels, and they become very fast then (at lower power levels), called speedlights.
Another resulting difference is that flashes at lower voltage for lower power become more reddish at low power (technically cooler temperature, but the art world calls it warmer color). Speedlights at truncated high power become more blue at low power (truncating the cooler red trailing-off tail of power). But White Balance correction is important for flash, there is no one color of flash, it typically changes a bit with power level.
I don't know, but suspect that these Godox may be speedlight construction, meaning being faster at low power whereas most studio "flash" are slower at low power. The Godox manual does not specify duration speed at each power level to know which it is.
Is there a meaningful difference between monolight and studio strobe, or is this just an example of a couple of product lines overlapping?
The terminology is similar, but not identical. In common usage, strobe most typically means a monolight, just as "flash" most typically means a speedlight. But a strobe or flash is any light that fires a brief burst of light, vs. being a continuous light.
But studio lights can have separate power supply and head(s) or an integrated unit that contains both the power supply and the flash head. The former are known as "pack and head" units, while the latter are known as "monolights." So, monolights are a type of strobe, just as speedlights are.
The Godox MS and SKII product lines do overlap a lot, but I think you may also have stumbled over the coincidence that Adorama rebrands the Godox SKII series strobes as "Flashpoint Studio" and B&H possibly attempting to match that naming to catch any similar search patterns. :) Adorama rebrands the Godox MS series as "Flashpoint BLAZ."
Besides the self-contained power supply on a monolight, I would say that it must have a modeling light. A strobe could still be called strobe without one.
Probably the size and power could be expected to be bigger on a monolight, but as there are even speed lights with decent power, probably not.
