Re: M$ should be paying us!
Classic Shell's performance became wonky in later updates to Win 10 as the devs of Classic Shell had discontinued updating the program.
I'm using StartIsBack - feature-rich, lightweight and buttery smooth. It is exactly what freshly installed Win 10's Start Menu should have been.
It's up to you if you wish to pirate StartIsBack or pay money to purchase it and support the excellent work done.