Yeah, it's very subjective - the above has been my experience, but I wouldn't argue that it will necessarily reflect anyone else's.
But for why I go so long without touching the UI code, it's just because the project is a 3D voxel game and there's a lot of big complicated parts to work on that don't involve any HTML UI.
This is a very interesting point, because my experience is quite the opposite.
Most of the time changes to the apps that I typically worked on (ERP/CRM platforms) involved both DB migrations, as well as back end and front end work. And with the front end, changes to the logic almost always resulted in changes to the template, even if only within a single component. The only exceptions to this were validation changes (changed logic only) or visual bugs (changed template only).
I wonder what qualities of the system design this points towards, apart from coupling.