They abandoned the NEX branding a long time ago, but they released a couple of APS-C Alphas at the end of 2019. I bet there are more to come, unless they're going to drop the <$1000 consumer market.
Besides this looks like a product team that got fired or didn't get renewed or something. There are contemporary Alpha cameras that are still getting updates, but the NEX was just a flash in the pan.
I have two Sony cameras - an Mk1 RX100 and a A7R III, both acquired shortly after their initial releases. I don't think I've ever updated the firmware on the RX100, and just once on the A7R III (I believe it was to get the uncompressed RAW capability), mainly due to laziness. But for my amateur level use, I don't think I've ever had any problems.
There have also been some updates that e.g. allow better use of the camera as a webcam.