I'm not yet "elderly " -- contrary to what a troublingly large fraction of younger software developers seem to believe -- but I do have occasional issues with touch screens, for several reasons.
They behave unreliability when I use the fingers on my left hand. I play guitar, so I assume that callouses are the issue. Older folks often have calloused finger tips; it's somewhat inevitable.
I often make or repair things, as well as work in my yard. At the very least, this often renders fingerprint recognition useless for days or sometimes weeks at a time. Sometimes my finger tips get scuffed enough that it affects touch screen use, too. I wear gloves when I can, but that is its own issue. "Screen friendly" work gloves don't stay that way for long, and aren't great anyway.
I also live in a northern area, so for about half the year humidity is very low. Even drinking plenty, and using moisturizer, my skin gets dry enough sometimes to make screens unresponsive.
Of course, we also get actual winter here. Even the best "screen friendly" gloves I've tried have been mid at best, just as with work gloves. Certainly not good enough to rely on.