From my experiences 30 years ago when the original mini, mk 2 escort etc wasn't a classic, but the best most folks could afford to run, I would say mechanically yes they are much easier to learn what's wrong and to learn how to fix new wheel bearings, bushes, steering rack replacement etc, BUT. and it's a big BUT, unless you can strip out bodywork and replace rusted panels and overhaul with welding skills ( not just surface rust but big panel and structural rust), then don't even think about it.
Or find one that's been renovated, even crudely but so long as it's solid.
Pity really cos there's a lot to learn about carburettors and the like, no catalysts, no fancy electronics, dodgy ball joints, grease nipples, alternators that don't last long, etc. guess you would rely on specialists for parts? Not too many of these old cars around in scrapyards now like there was in the early 80, s! Was dead cheap for parts then and a few simple spanners got most things removed easily.
Find a dentists or barbers with a table full of classic car mags and read up first before taking the plunge.