“Is it any wonder I’ve been a Linux desktop user for over 30 years?”
I run an older Windows and use only the Office products and Keil development studio, and Terraterm for downloading to a device.
Where is the pain and uncertainty if I change to Linux desktop?
You can have both MS and Linux in the same machine if you like. MS for that ONE game or app you can’t live without. And more secure Linux for everything else like surfing, banking, shopping, etc.
Terraterm is just a terminal emulator. You have NO IDEA how rich THAT environment is under Linux. I think you would be more than pleased with those choices.
Given that information, moving to Linux should be rather painless for you.
I would start by putting a Live ISO on a flash drive and booting up to that, and see if you like that particular flavor. If not, you can always replace that ISO with another one and reboot.
That way, you can test drive Linux and it's different distros to see which one best fits you and the way you work.
It probably depends on what exactly you use computers for.
We changed and found Linux (Mint) to be very easy to use; the user interface is not much different from Windows. You just have to spend some time learning the little differences that do exist in some particulars of Linux programs. We’ve been very happy with it, never had a problem. I haven’t found anything I wanted to do for which I couldn’t download a Linux program.