This is a natural outcome of a combination of rising wages and dropping prices for finished products, plus, in some cases, increasing standards—for example, single-pane windows with glass held in by paste were really easy to repair but provided almost no insulation—modern windows are really hard to repair, but insulate well.
If we want repair-culture to come back we have to make everyone materially poorer first. Everyone who's not crazy-rich would know how to sew if a t-shirt cost $100 new and could be sold used for $50, instead of like $10-15 and $0-3, respectively. Nobody pays a cobbler $150 to re-sole their $50 sneakers—their $400 leather oxfords, maybe.
We stopped repairing stuff because stuff is cheap—it's not worth developing or maintaining repair skills to try to get another year out of the odd $20-$150 appliance, or tens-of-dollars pieces of clothing, or paying five times as much for floor trim that can be re-finished or repaired when it gets dinged up, over cheap crap that'll just have to be replaced if it gets damaged, when the labor to replace it's not much different from the labor to repair the nicer stuff. We stopped having experts repair stuff because labor is really, really expensive relative to goods, now. We just throw away the broken thing and replace it. The fix, if we want one, is to make stuff way more expensive.