Late to the party - I've finally saw it!
As others have said, it's completely bonkers. Fun, but absurdingly over the top. I think the best way to approach these movies is to imagine they're videogames. You're watching someone very good play the John Wick character and he's so good at it that he manages to kill all the enemies.
I agree with the comments above about franchise fatigue; the first movie was simple and brilliant - retired hitman gets his dog killed and wants revenge. And the second one was ok I guess, he has to honor a previous promise and it ends on a great note - "tell them Winston, whoever comes... I'll kill them. I'll kill them all". That's the premise of the third movie then and there, John Wick vs. Everyone! but then they went deep into the world building instead and the more they explained that world, the more they exposed how absurd and unrealistic it is.
The last hour in Paris was waaaaaay over the top. I mean, where is even the police? shootout around the Arch of Triumph? nobody at Montmartre (even if it's dawn) or at the Trocadero? and John falling out of a three stories building and onto a van and walking off easily, that's why I said it's best to imagine these movies are just videogames played by a pro that manages to get to the end
but it was not really worth 3 hours, I watched it over the course of two days actually.