The warning was for others like myself who might blunder into UE thinking it was an IDE, and not realizing it's really just "a bunch of scripts being called from a main loop".
The whole point of blueprints is that the provide a visual interface to link the underlying classes together in a fairly easy manner you can actually make a game with using blueprints only now you’ll be limited in various ways from not having the exact functionality you want in a given blueprint to having performance issues if you are linking too many blueprints together to perform a relatively simple action but they serve their purpose and that is to detach much of the high level game/level design implementation from the low level code implementation.
Software developers in AAA are just putting the infrastructure in place, the real show is driven by others, so game development IDEs are tailored for those skillsets, not writing barebones C++ code.
In any case for C# to easy game dev you have Unity which used C# as it’s base language.
Almost all game engines are written as bunch of scripts being called from a main loop so yes anything in UE regardless of what it is if it’s a graphical element or some piece of logic that changes the world state will be a self contained C++ “script” even the parts of UE that support higher level scripting languages are still then compiled to C++.