There are plenty of tech options for all classes - anything which summons minions for the opponent (and a couple of class specific ones (hex/polymorph) and Zephrys. While I agree it can be frustrating to play against particularly when you think you're winning then they have a huge swing turn, but to be honest the deck just isn't very good any more. It's just too slow in the current meta (imo).
There are ways to tech against this deck as mentioned above. (That work pretty damn well) And Rez priest is NOWHERE NEAR as annoying or cancerous as big priest was in wild. so uhhh. Yeah. I mean this endearingly and with tough love but... git gud
Rez priest is based on immoderate mana cheating, which in most cases feels unfair and frustrating to play against, and will always cause problems. Mana cheating is only acceptable on a small scale, under specific circumstances (based on risk and reward, like overload mechanic, where you "mana cheat" first, to pay debt turn later by loosing tempo). Heavy cheating, which gives you huge amounts of stats for a fraction of their true cost, will never be balanced and Blizzard must finally understand this.