I’ve done all of the same, including back to punch cards on an IBM mainframe. My first intro to computers was in 1969 using punch cards. I spent a large part of my military career working with computer systems and software development as well as all types of command and control systems and 10 more years working as a developer and analyst for a large company.
Now, I deal with college students who have long been users of technology on a daily basis who are not like you or I, with years of experience and daily interaction with an OS and interface. Using a specific technology long term ingrains habits and even minor changes in usability can be distressing for a lot of people.
I find Win 10 to be an easy transition from Win 7 or even XP but there are many, many on these forums, who do not find interface changes, even small ones, to be easy to learn and use. Again, Win 10 is designed to work optimally on a touch tech device. It can be easily used on a regular non-touch device but for many average users even small changes to how they have long done things can be challenging.
OK ...
Since you found Windows 10 to be an "easy transition" could you enlighten me as to what some of these scary differences might be? I'm really at a loss as to what you might be talking about. For that matter, could you explain how Windows 10 is "optimized" for a touch screen? Perhaps there's some sort of touch feature that I'm unaware of ... I've only used it for 10 months on a desktop/keyboard/mouse.