I wonder how many people still program modern game engines? Sometimes it feels like everybody just take the newest release of the Unreal Engine and drops assets

I wonder how many people still program modern game engines? Sometimes it feels like everybody just take the newest release of the Unreal Engine and drops assets and scripts into it. Just to be clear, I am not saying that there are no alternative engines, just that these things are so complex that there are very few people, who dare to compete with Unreal.