Unreal Engine is very much set up for a specific workflow and makes assumptions about how it will be used.

I don't want to defend Epic but have you used Unreal at all?

Theres a ton of different ways to use the engine. You can use blueprint for everything, which works, but coding it yourself can give better performance. Using the (sometimes pretty subpar) default nodes in the material editor works but writing your own HLSL materials or nodes can give better performance. Do you rely on lumen and nanite to "solve" your 5 billion poly objects or do you optimise them yourself?

Don't blame the instrument when the music is bad.