This is not in all cases, i found it generally pretty easy to jump between the c++ api of unreal and the c# api of unity. Managed to learn enough unity in a day to make a working game actually. Though when it comes to the API and scripting interfaces of 3d packages, that is a different deal, since i work with the c++ API…
I think the biggest hurdle is the bias you seem to be bringing. Drop that and learn the tools for what they are and you should be fine. The industry is anything but fixed in concrete and never changing. There always seems to be something new to learn, some new set of tools to master and some interesting apps to explore. A…