I think owning a modern vehicle for 20 years from new is possible, but to keep all the systems running as new will be costly. We did end up choosing to stick with the S trim on our new Jetta for a few reasons, but long term ownership one of them. SE+ models have a pano roof and long term ownership concerns. A few owners have had their roof explode, outside of warranty that is a $3000+ repair, yikes!
If one was looking to purchase new car and keep it for 20 years they should avoid such options IMO, unless they are willing to pony up the $$$ if something breaks. I'm fine with technology advancing as long as automakers still produce models with more reliable systems for owners that don't want all the new gadgets rolled in with every trim level. Wow, I sound old.
Also, it pays to do research! Don't go out and buy a new car without doing your homework. That shiny new "cute ute" may have just been fitted with a new gas sipping CVT (nothing against them) and 3 cylinder engine for the new model year and has not been proven yet. Don't expect 20 years and 200K miles out of a new powertrain that has yet to be road tested and proven. Remember, we are now the beta testers.