I'm going to have to give a hard disagree. I've been making my own engines for a long time, and have used many different engines for a longer time. Inheritance-based entity systems are often a pain in the ass to work with, a massive pain in the ass to debug, and tend to invite shitty hacks to get around the shortcomings of the inheritance model.

The article says that "Godot does composition at a higher level than in a traditional ECS", but I don't get what he means by that? Combining nodes with incompatible hierarchies is hardly composition, and is just what you typically have to do when using inheritance.

Inheritance-based entity systems are not always terrible, and even though I tend to hate them, I use them quite a lot in my projects where an ECS would be overkill. If designed for a particular project, you can usually be more productive, and write cleaner and less code with inheritance.

However, for a general purpose engine like Godot, that's a bad choice IMO. The flexibility offered by an ECS far outweighs all benefits of an inheritance-based system.