I would like to know how the fuck can any Grognard "gatekeep" any "kid" from playing 5e?
Keeping kids from playing 5e is easy. All you need to do is not run D&D for your children or their friends. Break the chain. Make sure your kids don't have any nostalgic memories of Dungeons & Dragons that can be exploited by woke corporations.
OR I can run 5e for my kid because I like 5e and like my kid and her friends enjoying it and don't have a political agenda for my role playing games.
People on this message board seem to care a lot more about politics than gaming it seems these days, and have also lost their sense of humor in taking their politics and gaming oh so seriously.
From a gaming perspective, there's far better games, settings, adventures, and sourcebooks to present to your kids than any of the 5e stuff, which is mostly mediocre corporate garbage. Almost any OSR product is better, certainly mine are better.
I mean, I get that as a parent you lose all perspective of coolness but giving them the megacorporation-approved product is like buying them the latest corporate faux boy-band record. You can do that, they'll probably like it because they've been programmed to, but if you wanted your child to be a real person and not an NPC, you'd introduce them to the Velvet Underground, or the Ramones, or the Smiths. Or hell, to Ustad Vilayat Khan, or Hamza El Din, or Vinicius de Moraes.