Are you on Windows 10's 2020 release? That doesn't resonate with my experience at all – macOS has been vastly more frustrating to deal with on 4K displays in my experience, constant reflowing and forgetting window states, takes forever to recognize the displays when plugging in or resuming from sleep, etc... I even have all of the pointer and icon problems you describe with the top bar. Sometimes, with a 4K display plugged in, it takes 10+ seconds to figure out how to use it. Meanwhile, none of that on my Windows machine!