If the blog referenced in the question is suggesting that selecting the film simulation prior to shooting has a material effect on the way an image turns out, it isn't suggesting that the image will somehow look different than if the same development steps are applied to the raw image data later.
Rather, it seems to be saying that by selecting a particular setting in advance of capturing the raw data it allows (maybe even forces?) the photographer to consider the final appearance of the image before the shutter button is clicked. Contrast that to the way many digital photographers shoot - which is to "capture raw data" and decide on the style, color, composition (via cropping), etc. of the image later. This often results in something akin to what Ansel Adams called a "...sharp image of a fuzzy concept."
There is much to be said for an approach to shooting in which the photographer considers the light, the composition of the scene, the colors, etc. and how they will ultimately affect the end result before pressing the button and making an image. It's similar (though not exactly) to what Ansel Adams was talking about when he encouraged photographers to 'pre-visualize' how a photo of a specific scene could turn out and then adjust the way the scene was shot to get that 'previsualized' result. Adams was also referring to the ability to "see" the limitations of the film/development/paper as those limits were applicable to a scene which one was considering. But the referenced blog only hints at that and never really allows the completed thought to bubble to the surface.
The blog referenced in the question doesn't really seem to say much of anything very clearly. It's not obvious what the point of the entire thing is, unless perhaps it is to try and make someone feel superior to everyone else for using Fuji cameras with built-in simulation of some of Fuji's most popular films.
That makes me wonder, is there any difference between the following:
- A Classic Chrome jpeg shot with the camera on 'jpeg only'
- A Classic Chrome jpeg created by the camera with "Q" (in-camera editing) after the original picture was shot in Provia (jpeg+raw)
- A Classic Chrome jpeg created by Lightroom from a raw file that was originally shot in Provia (besides differences in noise etc)
Although it would certainly be possible for Fuji to apply different raw processing settings to an image captured using the "Classic Chrome" setting at the time it was shot compared to the settings used when applying a "Classic Chrome" style later in-camera to data already shot, it wouldn't make much sense at all for them to do so. They're marketing the "look" of the film simulations possible in-camera as part of their brand. It's almost a certainty that the exact same settings will produce the exact same result whether applied to the raw data as it is shot or applied to the raw data using the in-camera editing feature after the fact. This is assuming the selection of a particular style does not affect the exposure settings (ISO, shutter time, aperture) used to capture the image.
When importing the raw image data from the Fuji camera to a third party raw processing application such as Lightroom, though, it's just as almost absolutely certain that the processing applied will be at least slightly different from what would have been applied in-camera using Fuji's own algorithms.
The actual "recipe" for the film simulations aren't really being included in the raw image data. Lightroom is just identifying the particular camera used and offering the same list of choices as are offered in-camera for each particular model. Even if Adobe and Fuji are cooperating to make the results using Lightroom as close as possible to the in-camera results, there will still be differences based on the way the core Lightroom application (and Adobe Camera Raw that is running under the hood to do raw conversion in LR) processes raw data in general and from Fuji cameras in particular compared to the way the Fuji camera would process that same data itself. Adobe products, particularly, ignore any information in the metadata attached to the image that is not a standardized EXIF field. They have publicly stated this many times in many contexts.
Keep in mind that the sensors of one Fuji camera model might be different from the sensor in another Fuji model. To get the 'Provia' look with the sensor in the XE-1 likely requires slightly different settings of things, such as color channel multipliers, than getting the 'Provia' look with the X-T2 when both shoot the same scene under the same lighting.¹
It matters not if you shot the image with the X-T2 set to 'Provia' or to 'Classic Chrome'. The actual raw sensor data will be the same in either case. If LR or any other raw viewing app is set to use the JPEG preview image generated based on the in-camera settings at the time the image is captured and appended to the raw file by the camera, it will affect the appearance of the preview of the raw file when viewed by any device (including the LCD on the back of your camera) that uses the JPEG preview. But the processing used to create the preview JPEG will not have any bearing at all on the actual raw image data used by Lightroom or any other raw processing application to render their own interpretation of the raw image data.
So ultimately the 'Lightroom' version of 'Classic Chrome' might be very close to the Fuji version of "Classic Chrome'. Or it might not be all that close. You'll need to judge for yourself if it is "close enough" for your purposes or not.
¹ I'm a Canon shooter who regularly uses three different bodies (5D Mark II, 5D Mark III, and 7D Mark II). I've also regularly used three other Canon EOS DSLR bodies in the past. The calibrated presets I use in Canon's Digital Photo Professional 4 for venues in which I regularly shoot are slightly different for each body, even though they are all used under the same lighting. This is true not only for color calibration, but also for contrast/shadows/highlights/etc. To get the same 'look' from very similar but not identical sensors one must often use slightly different settings with the same raw converter application.