Because of Linux's Fragmentation there are so many different UI being created right now and so much more experimentation. There is KDE with endless customization, Gnome for the people who are okay with a more opinionated UI, Cosmic the completely new Desktop Environment and of course the good old lxde. I have to use Windows at work these day and every single one of these makes the Windows feel like it's more suited for Old People because of how slow it can be.