GT550 rode like new at 70k miles and 27 years. Okay, the valve seals had probably hardened off a tad (as much with time as with miles?) so it smoked a little when starting, but a top end rebuild would've probably set it up for another 70k.
The CBF500 engine was supposedly designed for 250k without rebuilds. Not many end up doing that though.
Any bike would get through a good few obvious consumables in that time - tyres, chains, sprockets, and maybe less obvious consumables like wheel bearing seals. Seals especially seem to have gone down hill now that car and bike makers all seem to have ditched garter sprung lip seals in favour of crude plasticky jobs - neglect the seals and/or get keen with a jet wash and you're looking at wheel and head bearings from as little as 10-15k.
My gixxer has seen off one set of head bearings already, but not through seal failure. Suzuki fitted unique and rare ball races better for feel (not sure anyone but a racer could tell) but just not tough enough long term. I don't know if the other gixxers have gone down the same route. Now mine has tapered rollers instead so I'm hoping not to have to touch them for at least another 30k...
Yes, some bikes will give folk some hassle if kept beyond 20k, but it's mostly avoidable.