Unreal is similar. All of the gameplay code runs on a single thread. The game framework tricks you into building slow OOP stuff by default with far too much poi

Unreal is similar. All of the gameplay code runs on a single thread. The game framework tricks you into building slow OOP stuff by default with far too much pointer chasing. You can easily make an Unreal project that performs worse than the equivalent Unity project. In fact, many do! It takes effort to release a well performing game using either engine if you have a non-trivial amount of "stuff" going on. Luckily Unreal comes with fairly advanced profiling tools so you can find where the problems are.