I use multithreading when appropriate, like saving or retrieving data in the background or event management, or processing tasks that can be done more efficient

I use multithreading when appropriate, like saving or retrieving data in the background or event management, or processing tasks that can be done more efficiently in parallel, but otherwise I don't usually use it, no. I definitely default to not using it until I'd get an obvious benefit out of it. The big one of those three when it's just my own projects is retrieving data. I tend not to work on complicated enough projects on my own that would require the other two all that often (and my side projects are usually games with relatively simple graphics).