I think this has been a basic split in the TTRPG scene since nearly the beginning, though I think indie games have become significantly more popular in recent years.
There was the "D20" period, in which they made an earnest effort to generalize D&D's core mechanics. But through most of its history, I think D&D has tended to emphasize its specific or idiosyncratic features. "System mastery" is closely related, but it also plays into something like nostalgia.