Classification of playstyles for Tabletop RPGs is underdeveloped. It's obviously useful when trying to find a system or group that you would fit in well with to be able to describe what you are looking for in a game. Meanwhile, you go on roll20 and look at the page for figuring out a system, and it just has a single axis: rules-light vs rules-heavy. Not that it even bothers declare it as a spectrum: it just groups all versions of D&D and its derivatives under a single "rules-heavy" umbrella. Go look at 3.5e and compare it to 5e (or fail to because the former isn't under a restrictive copyright and the latter is) and tell me with a straight face they have the same amount of rules content.
Never mind the amount of rules, don't you think that maybe what those rules focus on would be useful information to convey easily? I've at least seen a small amount of effort here, though it seems rarer when talking about the design of a game than I think it should be. I've seen it primarily with three categories: focusing on the story, focusing on the gameplay itself, and focusing on the world being believable (narrativist/gamist/simulationist), with possibly an extra for the casual player just wanting a good time with their friends. Now maybe if I was focused on the story I wouldn't be seeing an issue with these categories, but to me this lacks critical depth in the gamist category. It fails to distinguish between playing a game because you want to see the action between the most optimized characters somebody can achieve, playing because you want to see your own characters become powerful, and most importantly to me, playing because the game mechanics are interesting and you want to see what can be done with them. Playstyle classifications that are not used for TTRPGS have these distinctions (Magic: the gathering, for example, uses both pretty much this set of divisions while also having an independent axis for how much those preferences then toward mechanics or flavour), but in my experience they haven't come up when trying to find a workable group or system.
Part of why this bothers me so much is that, at least in my corner of Tabletop RPGs, it's very noticeable ingame when you have keywords that can clearly define what sort of thing is going on, yet apparently nobody actually extends that to out-of-game activities.