As the github release notes state:
1500 contributors! 12K PRs!?!4 years of development.
12,000 merged pull requests.
7,000 fixed issues.
1,500 individual contributors across engine and docs.
The Godot 4.0 release is by all metrics our biggest release so far.
No stone has been left unturned, all parts of the engine have been
modernized, refactored, overhauled, rewritten, redesigned.
Godot is a joy to use is you haven't tried it already and its very lightweight compared to Unreal, Unity and most other modern game engines whilst rapidly closing the gap on features and performance with the industry standard engines.
https://godotengine.org/article/godot-4-0-sets-sail/