I play only games that the author calls “rules lite”, and i think they are missing the point entirely. I would call the lighter games “collaborative games” and call the more D&D-like “pre-structured games”.
We dont play these games because they are simpler (though they are), more straightforward (true), or easier to teach new players (also true). Instead we prefer them to D&D because they are more fun (for us).
It’s not about having fewer rules. It’s about having rules that each make the game more fun or exciting. Most D&D groups houserule the system so much that they arent using half of the game’s mechanics, and the other half are heavily modified. The resulting game hardly resembles the one described in the source book, and ends up being slow, tedious, and limiting.
I’d rather play a game that rewards you for learning the actual rules, a game whose mechanics are cohesive, additive, and fit the vibe at the table. I want mechanics that help me be more creative, and help the table create a better and more compelling collaborative story.
D&D is also designed for 4-6 hour sessions. My group does weekly 2 hour sessions, so 5e combat can last weeks. By the third session of combat the players are starting to forget the stakes of the fight.
The games i’m talking about are those like Blades in the Dark, Dungeon World, The Sprawl, Armor Astir, etc. Any serious DM should at least read Dungeon World and Blades in the Dark to get an idea of the philosophy behind these more collaborative games.
My group recently did a campaign of the Avatar the Last Airbender RPG and while it wasn’t my favorite, it wasn’t bad. I liked the system much more than 5e.
My favorites are when the mechanics are about the story. See combat in Dungeon World for example.
You are still rolling dice, crunching numbers, and rules lawyering (the dice take precedence over all) but you are arguing about what happens, not how much damage someone does/takes.
In those games, the fluff is the crunch and the crunch is the fluff, and most of the time they are one and the same.