No most bugs aren’t hard to fix at all. You can see the fix for this one is no exception. Once you found the bug the actual code-wise fix is often something that takes no more than five minutes. Another joke along these lines is you would be amazed how many bugs can be fixed by merely flipping two lines of code. 
I’m wondering since we have a rather different experience with Plasma whether it is really Plasma itself causing the trouble or merely exposing it. I mean there are reports of issues that show up in Kwin or freeze the desktop but the real source isn’t a bad Plasma version but more likely a change of the Nvidia driver? Perhaps i have a stable experience because i’m only on an Intel iGPU?