Respawns use of Source 1 was a similar story, they ended up rewriting practically everything in the course of developing Titanfall and Apex Legends, to the point that it's almost unrecognisable as Source at this point.
If you haven't taken a look at S&box recently it's looking a lot more like Unity now. https://sbox.game/news/scene-system
Also, indie games are a billion dollar market. Maybe it's time to stop using it as a synonym for "not serious." The consumer doesn't care that Undertale was made with Game Maker.
>There's also O3DE which last I checked isn't ready.
Literally no one cares about O3DE.
To me "indie" is usually more a reflection of budget, which heavily impacts graphical sophistication, size of the game (as in how many levels, how many hours of play, etc), and usually means the price of the game will be between $5 and $30. AAA I expect $60 and 100+ hours of playable content. Indie game I expect 5 to 6 hours and I'm pleasantly surprised when it's more. When it comes to choice of game engine, that usually means they prefer less flexibility but more simplicity and "free stuff" from the framework, whereas a AAA game might prefer maximum flexibility, but that comes with complexity. As in all things it's a budget (time & money) tradeoff, not necessarily an "are we serious" tradeoff.
My experience is much more the opposite, with plenty of indie games providing many hours of actual gameplay (including replayability) and plenty of AAA games inflating their runtime with long cutscenes and other fluff (or milking people for all they're worth through live service).
There was a time when Unity was the 'indie game engine' as well. Give Godot some time (especially since it's progress seems to be picking up steam.)
> UE5 on the other hand is leaps and bounds greater
UE5 has the benefit of standing on the shoulders of giants, not to mention giant-sized pockets of cash to spend on developing it. UE has been around since 1998, so we're talking a quarter of a century of development leading up to what UE5 is today. It also has the added benefit of having been used for a huge number of different games, so there's an additional level of refinement in the toolset that it offers, since it's had to adapt to suit so many games.
That's still the case, depending on how you define indie. I'm not aware of any major AAA game made with Unity.
Some Unity games I know of:
Genshin Impact (maybe the closest to "AAA")
Rust
Fall Guys
Escape from Tarkov
Cuphead
Fallout Shelter
The Elder Scrolls: Legends
Magic: The Gathering Arena
Super Mario Run
Mario Kart Tour
Hollow Knight
Untitled Goose Game