I personally am a big fan of tekkub's works (some of them anyway). I've used VendorBait, Squeenix, Tek'sLoot, Tekticles and GnomishAuctionShrinker back in time when they hadn't have any possible alternatives "on the market".
It's well known and widely acknowledged that Tekkub is a born geek, he's weirdo and seems totally rude to newbies but it's offensive to people only who treats it seriously. Despite these facts, he's a masterful mind with uniquely brilliant addon ideas but unfortunately -as you mention- he stopped playing WoW years ago, and not really willing to update his own addons anymore. Lucky to us, many fans who are not greek to lua coding usually maintain his gems and release various fan updates or lua fixes for them.
I still use 2 of his addons, namely the GnomishInboxShrinker and GnomishVendorShrinker. The first one works just fine in 8.0 (maybe produces lua errors, idk) but I couldn't get rid of the Vendor Shrinker past the BfA prepatch as it produced various bugs, such as vanishing the whole vendor panel, etc.
I found out there are some user-made fixes by Shauren and MuffinManKey on Tekkub's github page so I was able to finally fix the addon for 8.0 by using their help:
https://github.com/TekNoLogic/Gnomis...Shrinker/pulls