Because we are limited by our perceptions of time (and causality as well) doesn't mean we shouldn't wonder what could have been before the start of the universe. Maybe time started when universe started, or maybe time always existed and was super slow or literally paused at singularity - the gravity is so high (way more than the gravity of a super massive black hole) that time had paused. So maybe there was something before the big bang and I don't think 'talking about that makes no sense' should stop us from talking about it :)
I am also confused a tad about the point I wanted to make though, lol. Maybe causality and time is perceived differently in higher or other dimensions that we do not perceive as of now in our human level of evolution. So the assumption of causality exists only due to time being present could be something relative to our perceptions and not true
So is causality—I'm not really sure what your point is.