I recently tried out LTSC again in a vm to see how W10 has progressed. Apps take a long time to open. I thought it wasn't registering the clicks or something, until 30 seconds later it opened it 3 times.
Start menu takes > 0.5 seconds to even begin animating. Disabling animations actually makes the lag subjectively worse.
I installed W7 a few hours later to compare, and I was amazed at the difference in responsiveness. I'm talking like 10-20x faster.
I bought 5 year old netbook recently and it didn't have the resources to open W10's start menu. (Well, it could, but it took three minutes.) Did a fresh install of W7, and like magic, you can actually use the computer again.
I don't use any version of Windows anymore, but I'd like to be able to. I'm sad support for W7 will be ending soon.
With classic theme gone, and everything so slow, the best Windows desktop experience for me in this day and age is XFCE.