Yeah it’s not completely seamless. IDK if there’s a possible fix. That’s just C++.
Unless there’s something about C++ I don’t know. But I’m also sure epic would’ve figured that out.
This has nothing to do with C++. The error is coming from UnrealHeaderTool, which is entirely under their control. Epic is just enforcing the best practice laid out in the documentation for TObjectPtr that it shouldn’t be used as a function parameter or return. They can’t do anything about functions that aren’t reflected, which is why the error only shows up for UFUNCTIONs.
With 5.5 and 5.6 they’ve added a lot more implicit conversions between raw pointers and TObjectPtr. As well as implicit conversions between containers of them. There should be fewer and fewer reasons to write functions (even unreflected ones) that take those types.