I kinda disagree, there is still a lot of waste even with the best bike brands. Hydraulic brakes are probably my biggest gripe, it's basically impossible to rebuild 4 piston calipers, and that's if they even have replacement pistons/seals to begin with. Hope and SRAM are the only two I know of that have pistons readily available but they are also overpriced to hell (it costs around $100 for 8 pistons, almost the same price as replacing the calipers entirely). Magura, TRP, and Shimano make everything in-house but they only supply parts to rebuild the levers, the calipers are basically just wear items.

Dropper posts, carbonfiber parts/frames, the 3 different hub "standards" being used, and non-standard sized bearings are all adding to the irrepairability of bicycles. And that's before you factor in that Shimano and SRAM are hell bent on using electronic shifting and shoving wireless bullshit on all their products.

Yes, a good bicycle is repairable and will last decades, it's just getting harder and harder to find new bikes that are good.