There still seems to be a market for repairing high end stuff. Shoe repair and clothing alteration stores haven't really gone anywhere
I suspect it's declined pretty significantly--in fact, because people wear fewer shoes that can be repaired and wear less tailored clothing. But of course there are still tailors and cobblers (who are often a good place to get backpacks and the like repaired) are still around. Many laundry places will do minor repairs as well.
In the anecdata department, the last time I took something into REI to be repaired they told me they didn't do that any longer and to send it to Rainy Pass in Seattle.
>cars need much less maintenance these days.
And, especially if you lived somewhere with snow and salt on the roads, they mostly lasted about 50K miles before they rusted out. Growing up, it was an unusual car that made it to 100K.
That said, minor repairs of otherwise functional gear can make sense. I'm generally in agreement on electronics. But I fairly commonly repair or have repaired hiking or camping gear for example that just needs some stitching to get back in working condition.