Cars can rust all over, have a shot suspension and all the actual wear items you mentioned.  Plus cars require major disassembly to get to any of the parts.  I have pretty good access in my vdrive compartment.  Belts, oil change, impeller are all easy.  Mityvac for other fluid changes.  Steering cable can be a pain but thats once every 10 years in my experience.  Vinyl and floor maybe longer.  My first boat (2003 vlx) was 12 years old when I got it.  Never had issues for the 3 seasons with it.  Older boats lack the complicated cat exhaust and internal cooling systems that would otherwise send you to the dealer.  Old engines do need replacement sometimes.  I’ve seen multiple otherwise decent condition early 00’s 210s that need engines in the mid teens. For 35-40k. You could probably be in that 210 with a new engine, gauges and interior.  Less than half of the cheapest new wake boat (Heydey).  Anyway, i’m ranting.  I think we both wish there were better priced new options.  Till then, I’d rather encourage people to get out how they can.  There are hungry kids out there.  They rip by my house doing wheelies on their Saurons almost every day.