I mean who knows! you could check back here tomorrow and see: ta daaaa ****'s banned! I'm still thinking about it....it's actually a really tough thing to call because it COULD potentially have a domino effect of "okay...well...is THIS variation banned? what if I throw in a footstool-iceblock in there?" and then you have the all too shltty prospect of destroying so much of a certain character's metagame that there aren't many options left simply due to legality
On the other hand, there ARE ways around getting grabbed by ICs depending on what character you are. I just think that very few people have solid experience against people who can use Climbers in such a way, so they're very ill prepared to avoid the setups that ICs will use to grab since their grab range is actually quite small [but their dash grab seems crazy good? I have no idea, never used em]
Maybe some characters will just have a ******** time against it. There were matchups in Melee where, essentially, getting grabbed = death. And while ICs can do this to everyone [!!!!!] at any percent [@_@!!!] with enough practice and knowledge, maybe the majority of matchups for ICs are ones where it's difficult for the Climbers to get the grab.
But despite those difficulties............then you hit that one crucial issue: all it takes is one grab. And unless you're on some oddly shaped stage or a moving level, you pretty much have to hope the ICs player simply messes up. Not even Waveshine-"infinites" against the few characters it really worked on were so broken that one use of that tactic can guarantee a stock-loss with perfect execution