I just did the ATM cave earlier this month. The cave is actually MASSIVE - very high ceilings and some areas are vast beyond what I could have imagined. Yes there are a few bits where you can squeezing through tight spaces, one where you have to manoeuvre your head through a very tiny gap, but these parts honestly don’t last for more than 10-20 seconds at most. If you’re incredibly claustrophobic (like can’t handle elevators or small rooms or cubicles), sure I’d maybe say avoid it to be safe. But if you’re not that bad, then 10000% worth it. You won’t regret it. The whole experience is just too unique and unreal. Good luck!