Where are you getting that? It's the basis of your entire argument and there's nothing to back it up. The loot box model is relatively new and we have a plethora of successful games (most) which don't use them at all.
In 2019, it costs £60 (or more for a "gold edition" or whatever). It isn't finished, has colossal bugs that require 50 GB patches just after launch, barely has a story (because listening to 13-year-olds shout ethnic slurs at one another is the new having a well-written story—and every developer thinks stories are passé and we all want "Live Services") and then tries to use psychological tricks to try and induce a gambling addiction.
I opt out and play the old games from the 90s and early 2000s that don't do all this BS.
And it is not like all games that have loot boxes games are f2p game. Quite a bit of them are full price games + lootboxes
edit: And let me point out, you can make money online without lootboxes, plenty of companies do, so it's not as if the revenue stream completely disappears.
And once your art budget is in the tens of millions, 'less detailed' is often a pretty small difference.
I only got my first game system, N64, at the end of the 90s though.
I think my, apparently false, view comes from getting in well after launch on N64.
Pretty much everything fits these patterns of reduction to the basic animalistic appeal: movies, music, clothing/attire, dating apps, even our politics. Its just easier and more effective to appeal to the limbic system than to figure out something new and profound.