My 1999 Merlin Road standard Ti frame is as good as the day I picked it up at the Merlin factory in MA in '99, as is the Time Equipe carbon fork. I've ridden the bike daily for near 22 years. The frame/fork is great but finding parts for my Campy 9 speed is harder and harder.
Most bikes last 'forever' if stored properly and cared for with some regularity. I repair bikes as my local LBS and am always working on old Schwinn's, Ross', etc. from the '70's and earlier. Most are in awful condition but are made rideable and work very well even after sitting in a shed for perhaps decades. New tires/tubes, chain, cables/housings, brake pads and a good tuneup restores then to good working condition. Can't do much for rusted rims but you'd be surprised what some steel wool will do.
It depends on what the expectations are for the bike. As a neighborhood cruiser they work just fine.
Old 5 speed friction stuff lasts forever or at least they seem to.