I have to say, I'm predominantly impressed with modern technology, but there have been a few balls dropped when 'moving forward'. I'm a huge fan of the automotive footswitch dimmer. I've always had older cars, my '01 van is the newest I've owned by 10 years, the majority of them being 60s/70s rigs. Why it had to become part of the column jumble is beyond me.
.22 rifles. I don't know why, but it seems like after about '80, firearm manufacturers REALLY started cutting corners on rimfires. Probably Reaganomics, but regardless, my old Marlins and Remingtons will shoot rings around new ones, and the only trigger work I've ever done on any of them is polishing mating surfaces to slick them up. I guess rimfires are thought of as a 'kid's rifle', worthy of cheesiness, because other guns have improved dramatically since .22s started to suck.
TVs. My first good tv was a Sony Bravia CRT, flat screen, 1080p (36", I'm pretty sure, the SOB probably weighed 100 pounds). It's a drag that it quit on me, because its picture was every bit as sharp as my new 4K LG, with way better contrast.
Specialty shops (music shops, gun shops, record stores, bike shops, etc.). They've all gone downhill in the face of the information age where you can buy stuff without putting your pants on, because of fat, lazy Americans.
Cigarettes. I don't really smoke anymore, only when I drink beer, but the second 'fire-safe' cigarettes became a thing, I quit liking them. Some friends of mine and I bought like 10 cartons of the old, non-FS Camel studs when we learned that this garbage was what we had to look forward to.
Beer. This is a cultural trend, and it may or may not die out, but nowadays every beardy hipster in North America is making 'craft ales', and there's a good reason there didn't used to be a market for coffee/beef stock/kangaroo smegma imperial IPA. It sucks, and no amount of hipster douchery will make it as good as Sierra Nevada Pale Ale or, if you're broke, good ol' Pabst.
In short, virtually everything. New stuff is pretty universally 'better', but a lot of the time the inadequacies of (and remedies for) old tech makes it more desirable and often 'better' for the task at hand.