I think it adds an extra layer of strategy in the game, especially in MK11 where they cost defense meter, since using one could make the breaker unavailable for a limited period of time. I'm okay with them as long as they have the same properties no matter which character uses them and they are usable only once per game. Interactables that can be used extra times and differently depending of the character like in Injustice is a dumb concept to me.
I understand why some people want them to be turned off, especially because a certain type of interactable will be available on the left side (let's say a throwable interaction) and the other side will only have a jump or grab interactable, so the player starting facing right will have a slight advantage. But I think that picking an arena is be part of a strategy. But, even used as a strategy, interactables are a double-edged sword. For exemple in MKX I like to pick Jinsei Chamber because I love the aesthetics of the arena, but also for the fountain interactable at the left corner of the arena that acts like a command grab. I can use it when in the corner to free myself from it, or neutral duck it on a read when my opponent is in the corner and full punish it. But, like I said, it's a double edged sword and it is not rare I get disadvantaged by the very interaction I wanted to use when I first picked the arena. And that's why I believe that counter picking in NRS games should also include stage selection.
But since interactables are part of the gameplay, it would be more interesting to have arenas without any interactions in the arena pool. We have like what ? 15 arenas in MK11 ? Then make 5 arenas without any interactions, I think 1/3 should be a decent number. Or make one or two with the exact same interactables at the exact same place on both the left and right side have a symmetrical arena from a gameplay point of view, like MKXL's pit.
The only thing is that they should be balanced this way : low risk interactable -> low reward, medium risk -> medium reward and so on... With Injustice 2, and even MKX, we saw that interactables are still not balanced. Corner escapes interactables needs to be highly punishable, more than any other interactables.