I am not too sure why everyone is saying that's okay.
Because the problem is that you can simply use a dying character as an excuse to execute another high-HP frontline character in the middle of a teamfight. Because to prevent 1 shotting after R is landed, someone HAS TO die, it's just a matter of who, and if the dying character happens to be behind an ally, that ally has to avoid their dying teammate or else they will be the one to die instead.
This is a really bad interaction. Because not only does it encourage the players to abandon their teammates, but that's minor, the biggest problem is that it makes teamfighting incapable to be stalled and worse, Urgot can kill your entire team as long as he lands a single valid R. It is not just a ranged execution, it's that once it's valid and due to its 2 stage mechanic, you have to disrupt your own team formation to prevent further damage done by potentially sending another full HP teammate to die as opposed to the one that's already on the brink of dying; and what do you get for being disrupted, enemy team can just rush you for being out of position.
It's a single-target execution that can very well be an execution of an entire team if landed correctly, purely because of the fact "anybody can take the guy's place", and its difficulty is about the same as landing Lee's Q or Biltz's Q, which let's face it, is not very high.
It's like Blitz's Q doesn't actually pull the target after contact, but it's a tag, and pulling only happens 2 seconds after the tag and it autopulls any champ in the line between himself and the tag, the first champ would be grabbed and insta killed regardless of whether or not they were even the ones initially tagged or how much HP they have. Just on a higher CD.
So it creates these dynamics: Yeah let's just land it on their dying player and voila, we insta killed their frontline because they can't get out of the teamfight too so we win as they now have no frontline. OR Yeah let's just land it on their dying player and voila, they are all out of position now because nobody wants to take the dying player's place, so it's clean up time.
A spell that's doing way more than it's actually intended to do is a problem, don't you think?