Yes, I’m aware. I’ve been playing since 1984 and seen my share of both. Perhaps it would have been better to say power gaming and metagaming like this spread and became wildly more popular with MMO culture.
I don't think it's a product of any specific culture, it's a natural consequence of TTRPGs becoming more mainstream. You see it in video games, sure. You also see it in sports. You see it in card games. You see it in kids reading "Choose your own Adventure" books and using bookmarks to backtrack to past decisions.
It's not even specific to games. You see it in car guys who built "kit" versions of supercars. You see it in fashion where people want gray market imports (or cheap knockoffs) of expensive brands. You see makeup tutorials on Youtube of how to use cheap products to mimic the looks of the stars. You see it in people who read spoilers before going to the movies.
When you get right down to it, the mentality that searching for outside help is "cheating" or "invalidates" D&D in some way is the outlier compared to normal human behavior. Its part of what makes D&D a niche hobby, and it's arguably a learned ettiquitte in addition to being a personal choice. As such, it's something that could only be less common when TTRPGS were at their least popular phase. And it's ineveitable that as D&D becomes more popular and more mainstream that players like this will become more common, because many mainstream players will bring this mainstream mentality to the game.