Getting appliances repaired is harder than it once was. Disposability culture drove many repair shops out of business. Many repair shops I and my family used to are now gone or dying. The guy who used to do sewing machine repairs for my mother is gone. The cobbler that used to repair my boots is gone. Furthermore, appliances that used to come with repair manuals no longer do, and finding the manual online is often a real chore. Fewer people will repair things on their own when manufacturers make it difficult to find even basic documentation.

It's a good point, but it's not really a failure of product design. Appliances themselves now are not any less reliable than they were in mid-century. There is no grand conspiracy of manufacturers filing down screw threads to make them fail.

I did not repair any of my fridges (they never failed in all of my adult life), but I did repair my washing machine (AEG 15y.o.) and my beans-to-coffee DeLonghi (10+ y.o). Both were very repairable and it was a matter of identifying the failure and finding the right part on eBay.

I don't think manufacturers are conspiring. I think this widespread behavior emerges from market circumstances and is not evidence of any sort of collusion between manufacturers. You don't need grand conspiracies to explain things like this, nor have I proposed one!

True, except there are manufacturers like Apple or Sony which won't provide genuine spare parta to retail people (tried that). Then you have to buy parts from "for parts" eBay auctions or counterfait/bad quality batteries from random Chinese seller...

How do you do maintenance on a fridge?

Back in the day it was routine to change the compressor, or even repair the failed one piecewise (bearings, manifolds). Refill the leaked coolant and braze the leaks.

You can still do that on most modern fridges, but it's not worth the effort with appliance prices now. They also don't fail often these days.