That was a tweet and a pretty ridiculous one. These sorts of caves are famously full of razor sharp rock that would puncture such flimsy inflated underwater structures.
I don't like Elon much (I think he's an ass to his employees), but he still sent engineers for free to Thailand and is donating materials that are probably not very cheap (rocket parts for the mini-sub thing). At least he's trying to help!
He is of course getting a lot of attention and it might be one of the reasons he is doing it, but he is definitely helping and he isn't receiving money, is he? I think attention is fair price to pay to Elon for his help.
I mean it’s a slightly better idea than the alternative, which is force weak kids who can’t even eat solid food because of starvation, many who can’t even swim, to try and swim through it. If that’s what happens the odds that even one of them make it aren’t very good.
Whatever the solution is doesn’t have to be perfect. Since the alternative is almost certain death, anything that gets even a few of them through part of the cave is better than nothing.
And if kept under pressure and combined with constant pumping it might last just long enough to get them out. It doesn’t have to be perfect. It just has to be good enough to get them part way or to make sure they don’t all drown.
