As an IT support guy...
doing small business and domestic, Windows 10 is a lot better than all before it.
Before hand if I had to rebuild a machine I had to use specific makers versions of windows to get it to match up with the worn out licence key on the back.
I don't have to go hunting for a dozen drivers any more.
It installs super fast. I tried using a Windows 7 DVD a few weeks ago...waste of life.
I don't have to wait for 348 updates to download and install like I did with a new Windows 7 install.
USB sticks and devices just connect and work within a couple of seconds.
Connecting to wi-fi networks is much faster.
The big updates are getting much faster and with a NVMe drive take just a few minutes.
Pre Windows 10 I was getting 2-3 machines in a week for virus clean ups. Now I get maybe 1 every couple of months and they are mainly scammers with Teamviewer but you have to check just in case.
If I get a machine in that just doesn't want to work in most cases it's the old HDD failing, not the OS. Thanks to Windows 10 that's an easy rebuild to a SSD.
So for me its 90% improvement. The only real issues I have are the annoying setup routine when building a Home version (just f*ck off). And not being able to just press F8 whatever to get into safe mode. Most of the fail-safe/recovery/repair features in 10 just don't work. It's quicker to just copy off the data and rebuild it.
I'm happy overall and the customers are too.