I think you sell older people short on what they are and aren't aware of. I think it's more that they see computer technology as a necessary annoyance of the modern world and not anything helpful. They used to manage their bank balance on a ledger in the back of their checkbook, and
that seems easier to them than having to sit down in front of the computer or use an app on a small screen that's constantly throwing popups in their face, either ads or little "helpful tips" about this month's new features.
I'm getting close to 60, but I've been programming and working with computers since in was in 6th grade. When I was in my 30s, paying my bills meant sitting down at the table once a month with my checkbook, stack of bills, and book of stamps. Open a bill, write a check, put a stamp on the envelope, repeat. It took maybe 15 minutes and was very easy. Compare that to opening a different website, with a different username and password and maybe TOTP code or SMS code, for each bill I need to pay. It's slower and more complicated.
There is no online payment method I've seen that seems easier to me than just writing a check. Of course I rarely write checks these days, so I use the apps and websites and feel annoyed every time I do.