I am having the exact same thing. was fine all day today, but this evening, the last few hours have been unplayable.

Clicking on NPC takes minutes to action, sometimes not at all. Earlier i waited over 15 minutes, still NPC didn't response, and I couldn't exist or log out because I was still doing an action!

This is a real game breaker. Seems to be happened to very few people, if any, around me though, which makes it even stranger. The only response people give is "I'm fine, must be your PC"

I took a video of it, suggest you guys do the same if SE need evidence.