>>28473010
You're right, I didn't mention non-ethanol rated fuel pumps and lines, but the point I was focusing on was that ethanol fuel isn't really going to hurt anything once it's in your intake. You won't burn up any valves or seats exclusively due to using E10.
>E10 will absolutely kill older engines even if they are driven a lot.
This still is still wrong. It can gum up and hurt original rubber components in some fuel systems, sure, but is almost definitely not going to harm the valvetrain. Even a lot of non-ethanol rated rubber is decently resilient and will hold up fine to it for the rest of the life of the line. It'll speed up the breakdown of the rubber, but you should be replacing rubber fuel lines and paper carb gaskets if they're 30 years old anyways.

I'd say the only cars I've come across that really, really do not like ethanol as a rule are anything with early mechanical injection. K-Jet especially seems to gum up pretty badly, pretty quickly in my experience. Mostly anything else will be fine unless your rubber fuel stuff is junk.