I'm really showing age here, but my first experience in computers was in Highschool with the CDC-6600 at the University of Texas. The UI was a remote teletype machine using ticker tape to save and run simple BASIC programs we wrote in class.
In College, at the University of Texas, we used the same CDC-6600 and the UI was punch cards which had to be hand delivered to the Computation Center where the computer was housed. This computer was the size of a small house and had less computing power than the average cell phone today!
My first exposure to the PC was the IBM Personal Computer XT (model 5160 or PC/XT) in 1983. It ran DOS 2.0. The UI was text only using a keyboard and a monochrome monitor with green text. I was involved in selling hardware and software for the IBM 4300 series mainframe. Back then, a megabyte of RAM for the IBM 4340 was over $2,500.00.
In 1985 I switched to the MAC computer with a Graphical UI.
My reintroduction to the PC was with Windows 95, and I have been an early adopter of every new Windows OS ever since. The introduction of Windows 8 was really different from anything else before, but very interesting. This was my first introduction to Stardock with ModernMix and Start8.
I have been using Windows 10 since its introduction and I agree with Brad that it is a very stable OS. I can remember a time when the PC would crash at least two or three times during the workday. I probably would have updated to Windows 11 except for the hardware restrictions. I have a 7700K processor in my everyday driver desktop. I am running Windows 11 on a test PC and find it tolerable. I could really care less about round or square corners, but under the hood, Microsoft has made some real progress.
I am using Stardock Start11, Groupy2, and IconPackager to make Windows 10 look and feel more modern. Stardock rocks!
As far as leaving it running or shutting down, my current PC has been running 24/7 since I built it in 2017. The only time it gets turned off is to upgrade a component or to clean out the dust. The occasional power outage will also shut it down! Most components normally fail when switched on. In my opinion, leaving things running is safer for the longevity of the components.