He very recently, maybe 2 patches ago, got a slight rework to some of his abilities that drastically increased his playrate and defiantly buffed him. Also support item changes, that were negative for champions like Bard, actually helped Taric alot and go well with his kit.
Thresh absolutely is telegraphed, that's how people can know when to flash to get away from his hook. It's a short delay but it is there. Plus, those two abilities (thresh and blitz hooks) only affect one person, it is not uncommon to get two people stuns, and if you position well (or they position poorly) you can even get 3 or 4 people in a stun.
Also, he not only brings a great stun but one of the most powerful teamfighting ults in the game (situationally), as well as a decent shield and crazy good heals, if you max his heals first (which is now viable after his Q buffs that I mentioned).
Since it sounds like you haven't played thresh or Taric, maybe your comment is invalid hun.
Yes, he might want a buff, but removing or reducing at all the delay is broken and stupid. It's already only one second, I've been able to stun tristanas and ezreals before they can jump away before (when their jump is up).