If you're talking car vs. car and leaving out 4wd, I will drive my 64 right through anything you can drive a modern car through.
Why would you drive a 50 year old car?
Economics...my car is worth more every day, yours is worth less.
Maintenance...my car is a pleasure to work on, yours is a nightmare
Resilience...my car has come through dozens of hail storms unscathed. Yours needs just a single good one to be totaled.
Personality...mine has character and individuality, yours is an appliance.
Pride...my car was designed and built by Americans, in America when we were awesome. Yours is a hodgepodge of bits and pieces sourced out from the cheapest vendors in the most obscure places on earth.
Longevity...50 years from now, my 50 year old car will be 100 and somebodies pride and joy. 50 years from now, your car will have been recycled a half dozen times and will likely be part of my guys snow blower or blender. This is inevitable due to the huge number of specialized parts used in todays cars. Things that control important functions will be discontinued and become obsolete as soon as their shelf traffic slows down.
Aggravation...as in, which warning light is gonna pop on next and keep your new car from passing inspection.
I could go on and on...but you get the idea.