A big reason why quick respawn is coming back is because it's a nice insurance perk for aggressive weapons. Because if you're playing, like you mentioned before: a tentatek, you can start the match off with a risky, but possibly rewarding play.
This type of play can be used in any mode honestly. Since the qr is here for merely having proper support to your aggression. And why it works on shorter range weapons like the Luna, is because it has to get up close. And a lot of weapons can shut it down before it even thinks about getting into that position. So, qr works like a "what if" scenario were to occur.
I think it's odd that people are starting to use QR again when Swim Speed will essentially do the same thing, but 100% of the game. Similar things to Comeback and Special Saver.
To be fair, swim speed can get back into the fight faster, but quick respawn is being used because you can start inking as soon as you spawn again, and most of the builds with quick respawn usually have swim speed in there anyway. So the player probably didn't want to deal with diminishing return. And since comeback is a head only perk, it's used side by side with it. Special Saver can be used as well, but it doesn't help you get into the fight quicker.