I think stuff wears out quicker than it used to.

Downtube shifter cables used to last forever, and if they broke, no worries. Brifters bend the cable at a much greater angle, and if the cable breaks in there, you could be in for a lot of grief. Result: You have to replace them much more often. I ride along the beach and find that I have to change out cable housings more than I used to. Indexed shifting means that friction is more critical than it used to be.

Chains are thinner I think they wear out and break easier than they used to. Older chainrings were often steel, and they didn't wear much. Newer ones are almost all aluminum, and wear quicker.

I think tire wear is about the same or might have even improved.

But I'll also say this: I think it depends on how and where you ride.

I don't know about the rest of you, but I wear out everything ... tires, cables, chains, cassettes, and chain rings ... a lot faster on the bikes I ride in the mountains than I do on the bikes I us on my relatively flat commute. that makes sense to me. The cables are used more often; the tires used on rougher surfaces, and at higher speeds on the downhills; the cassettes, chains and chainrings subject to more force when climbing ... particularly when standing up.

Either way, it's still a hell of a lot cheaper than driving. With a few dollars here and there for maintenance, you can ride the same bike for years and years without replacing it. You can't say that about automobiles.