Wasn't UU an RPG rather than an adventure game?

That’s a fair point. I suppose if I wanted to focus on the first person perspective I could have mentioned Myst coming out the same year as DOOM, though I doubt it was even the first FP adventure game.

It was really a blending of multiple genres. Was really ground breaking by for its time.

UU was an RPG. What adventure games became were either full hybrid 3D mechanics (Tomb Raider) and niche point and click ones.

Tomb Raider isn't an "adventure" game, no matter what the "mainstream gaming press" says. Monkey Island is.

It was a real time action-adventure game with puzzles. TR made point and click adventures obsolete as they drove a puzzle-event bound game with free exploration. OTOH, text adventures would still be featureful and playable as they achieved incredible things very expensive to do with graphical games.

If Tomb Raider is an "adventure game" so is Donkey Kong. Tomb Raider is basically a platformer like Donkey Kong but in 3D. Neither made actual adventure games "obsolete" because taxing your hand-eye reflexes is a different sort of fun than taxing your brain.

Also, definitively, what killed the adventure genre would be the PS1 survival horrors. You have everything there: items, combinations, loads of puzzles, action and a shitfed perspective. Silent Hill, Resident Evil, Parasite Eve...

Pretty much the definition of an old 'point and click' aventure with action points.

Alone in the Dark predates those by like 4 years though...

It does and there were also plenty of horror adventure games, but Alone of the Dark would also make the jump to RE-style survival horror.

TR has more to do than platforming, and more convoluted puzzles than DK.