I think IntelliJ has the best UI of all IDEs I've seen, it sure as hell beats Visual Studio (the paid one), it beats Netbeans, Eclipse.. What else?
VsCode and atom are simpler, but they just don't provide UI, for many setting you have to go to config files, and some functionality is missing outright.
Jetbrains products are my preferred choice for full-featured IDEs, but this is not exactly an industry renowned for producing snappy and pleasing interfaces. And since LSP has narrowed the gap, most of the time I don't require the features that would make up for the bad UX so the majority of my coding happens outside an IDE.
MacVim is my favorite when it comes to UX. It starts instantly and stays fast even on huge files. It's very customizable and works exactly how I want, including the layout of nested horizontal and vertical split panes.
I like being able to configure just about everything in just a single config file, but still getting an additional escape hatch for overriding OS default keybindings I want to use.
VsCode and atom are simpler, but they just don't provide UI, for many setting you have to go to config files, and some functionality is missing outright.
Can you think of an IDE with better UX?