The same thing happened to western superhero comics before the SJWs sauntered in; many of them were just violent snuff films in page format, all trying to ape classics like the Dark Knight Returns or Watchmen, and whenever you'd try to make a mainstream superhero comic for kids, you'd get laughed out, because the comics weren't being made for kids, but for adult fans well into their 30s or 40s. And the result was obvious; a shrinking audience that isn't expanding, became less and less profitable, meanwhile the toys, movies, and cartoons were selling, so the comic companies gave the funny books to the SJWs for some good PR points while they focused on the kid-friendly shit, leaving the 40-somethings to rot while they profited off things like the MCU or the cartoons.
Ok, just stop. The edgy adult comics shit didn't become a major trend till the damned 90s, and that was after indie comics were doing it in the 80s. But you're forgetting the entire golden and silver ages of comics before that. Comics were marketed at kids from the start, until kids were priced out of it due to speculator bullshit in the 90s with ridiculous pricing, a half dozen alt covers, etc. And as far as SJWs being in the comic industry practically everything Stan Lee was involved in revolved around oppression, slavery, equal rights, etc. Hell, the damned cartoons even Superfriends came out in the 70s, do I even need to mention the 60's live action Batman show being kid friendly? Come on man.
Maybe they'll sell a kid-friendly, Fortnite-style, free to play Space Marine arena shooter game with microtransactions for each Space Marine chapter design. Or maybe they'll commission some Japanese artists to make 40K/Fantasy manga/anime. Whatever works with the kids, they'll grab for it. Hell, they can probably make way more money with those two examples than with miniatures.
Have you never noticed just how many graybeards on dakkadakka, or even youtube channels(not the ones that jumped on the bandwagon during the covid bullshit) all talk about playing and painting 40k as a kid? GW has always marketed in one way or another to kids. Even back in the 80s(and up into the 90s) it wasn't much different than every rated R hollywood movie having a line of action figures associated with it marketed to 7 year olds(robocop, alien, terminator, Rambo, Starship Troopers, etc all had kids toys and some of those even had saturday morning cartoons).
Don't believe me? Look this shit up. Yes, RAMBO of all things had a damned saturday morning cartoon. Go try to watch any episode of Batman with Adam West and tell us that wasn't supposed to be kid friendly. And as far as doing a 40k manga or whatever.. I wouldn't be surprised in the least considering one of their largest and most expensive stores is in Tokyo with a fucking cafe, video wall, etc. and their smaller stores actually leave the demo tables outside the store so people can check them out because no one is going to steal the shit.
edit: For fucks sake, the entire reason the CCA(Comics Code Authority) existed since the 1950s was to act as a seal of approval for parents to buy kid friendly comics due to some of them becoming just as bad as the degenerate smut that scifi and fantasy pulp novels had been(think of the shit like Boris Vallejo covers from the 70s and 80s, and that being the store shelf friendly version of what the book was about). You really need to stop with whatever sources are trying to tell you the world was like prior to 2000 or whatever. Hell, the only damned reason Disney threw money at that x-men '97 cartoon recently targeted at 30 and 40 year olds was because how many of those people were fans of the x-men children's cartoon from the 90s.
and back to the 40k marketed to kids thing, remember Duncan Rhodes who isn't a nobody when it comes to 40k, and his "two thin coats" basically started as he painted his marines as utter trash when he was a little kid because... he was marketed them as a kid.
edit again: Fuck this. I just randomly opened an issue of WD(188 if you're interested) and 4 out of the first 6 fucking pages are kids in the store, playing, etc, with one kid winning some contest and getting some free shit. Get rid of this utterly misguided view that GW never marketed to kids before but somehow now only markets to people in their 40s even though they've been at this for 40+ years.
Yes, GW might, without surprise to anyone using a brain, change how they market their shit to kids as times change and the way kids interact with media changes. This is why they make plushies, made the warhammer adventures books for kids, have sold comics within recent years, have been toning down the "sex" part of slaanesh, and so on.
Also, you might want to look at some of the older catalogs, and then hit an inflation calculator as well. You can find things like single metal minis available for $1.10 from the 1984 US catalog... which puts them at 3.32 with inflation, which if you factor in needing a few dozen of the damned things(plus paying for shipping and sales tax, and paint) ain't cheap for an army of minis in the 80s. This was never a hobby for the "poor".