I was literally just emailing back and forth with a BF'er and said nearly the same thing. My shop knowledge goes a couple of years farther into the 90s, but the hard cutoff mid-late 90s is real. It's been a bear for me during Covid, I'm hitting a lot more off-road trail riding and had a few MTBs fall into my lap needing overhaul, whether on purpose or not. Some of the stuff - like linear brakes - have been super simple, but other stuff I've avoided all these years ... not so much.

That said, if they're looking to go new and not spend a fortune, I've found the Tourney, Acera and some Alivio stuff is relatively inexpensive to pick up and decent quality. You really, really need to be careful to watch out for knockoffs though. The market is flooded with counterfeits people are sourcing from Alibaba and other similar marketplaces, then reselling on eBay and Amazon. I've yet to see a pair of legit EF51 and EF65 levers in what's turning into an endless hunt for a reasonably-priced new or used pair of genuine black Shimano M591 shift/brake combo levers.