My grandpa was the most flexible-minded elder I ever encountered but even he didn't want to change the way he did things once he learned how to do something. He made the transitions from Windows 3.11 to 98se to XP well enough because I minimized the impact by using "classic view" setups and carrying forward as much of his software as possible.
He wasn't afraid to explore new things. Just that, once he learned them, he wanted it to be static and unchanging. Why would you change something that works? One weekend, I came home and he showed me the radio-fax kit he'd bought. Say what??? It was a receiver that plugged into the headphone jack of a shortwave radio on one side and the serial port of the computer on the other side. The software would record and decode faxes of weather maps that were broadcast over shortwave then print them on the DeskJet 500c. But, when this kind of thing became widely available on the internet, he wouldn't switch until either they stopped broadcasting or the software didn't survive an OS upgrade. I forget which. He didn't like using websites to get weather maps as much because they'd make small changes to the websites once or twice a year and he'd have to hunt for what he wanted. As inefficient as the radio-fax thing was, the process didn't change.
And he was doing online banking back in the 90s. No urging or input from me. I didn't think he'd be comfortable with it. But one day he was telling me how I really needed to look into this online banking thing. "It's great!" Heck, I only beat him to it by a few months.
I don't know if it's really just old people who are like that, tho. Way back in the before time, I signed up with a temp agency to get some quick money while I was looking for a permanent job. I did the Word and Excel tests because that was the software I'd used. Then I realized they wouldn't send me to a job where they used WordPerfect or Lotus123 unless I took and passed those tests. It seemed absurd. That would be like "Oh, we can only send you to jobs where you'd be driving a Toyota. You didn't take the Ford test." When I passed every word processor and spreadsheet test they had, the woman looked at me like I was a wizard. "Why didn't you say you knew those programs?" "I don't. I've never used them in my life. But a word processor is a word processor. They all do the same thing and have the same menus." "Wow. I'm not going to have any trouble finding you a job!"
I've worked with people in almost every age group who learned by rote and have no comprehension of what they're doing. I used to say most people 5 years younger than me or older are hopeless with a computer. And that was back in my 30s.