IIRC, all those engines provide an ECS that could be compared to entt.

Also, there is Hazel[0] which is based on entt and is the subject of an amazing youtube series[1].

IMHO, tinier means less features, at that point what could be considered comparable?

  [0] - https://github.com/TheCherno/Hazel
  [1] - https://www.youtube.com/playlist?list=PLlrATfBNZ98dC-V-N3m0Go4deliWHPFwT

To be comparable in size we should look at what they do. The three game engines originally mentioned have everything from physics to an entire visual IDE. A comparable smaller project is Godot not entt.

A comparable ECS implementation is what you’re after. Is entt tiny in comparison to similar projects.