That sounds like a modern bike is not built to last anything like as well as old bikes, my old ten speed racer I had BITD lasted me many more miles than that and the only stuff I bought regularly for it was tyres, brake blocks and spray paint (the paint was 'cos I kept pulling it apart and respraying it to match the bikes I saw racing on TV)
When I think about what's finally killed my bikes, it's usually frame failures.
Kirk revolution - drop out snapped off
Dawes Ranger - cracked bottom bracket shell
On-one Inbred - Rusted out Bottom bracket shell
Whyte 901 - broken seat tube
4T titanium - broken seat tube x 2
Ritchey logic - broken down tube.
Knowing what I now know (or more likely who I know), I would have probably attempted some frame repairs on the steel frames. Although I had one bike shop owner I trusted warn me about the Dawes a few years before it failed. He said it's a 10 year old (at the time) mountain bike, and 531 forks of that era weren't meant to take that kind of abuse. He'd had a few customers where the forks had simply collapsed.
The inbred probably lasted the longest. I reckon that must have done closing on 50K miles. Some of the others probably didn't make it to 5K.
Nowadays, I'm a bit more likely to look at the economics of it - including my time. I've just had an ebike fail. I can do all of the mechanical stuff (and have already replaced complete drive chain, brakes, tyres, tubes) - but can do limited trouble shooting on the electrics (I've replaced a charging port twice, charger twice, troubleshooted and fixed some dodgy brake sensors) - but it seems the motor, charging controller or something else has gone. That's potentially £200+ of parts not counting labour. It's done 3.5 years of commuting, complete with shopping etc in extremely heavy weather at times - and cost £350. It's replacement cost £363 - and I can transfer over any working parts from the old one over to it when they wear out. Pretty sure, I can part out some of the rest for around £100 too.
My spare commuter ebike, costing £400, has just done 2K miles and only had a set of brake pads and a chain replaced.