I agree, the issue with speculating about aliens in any way is that our imagination is hilariously limited. We are the only intelligent species we know of and we live in a very specific environment and have very specific needs, which has shaped the way we think and our way of life in very specific ways.

Everything we can imagine is just a remix of things we have seen before, and if there are aliens out there, it's highly likely they will be nothing like anything we know. Literally inconceivable to us at this point. Not just visually, but also in how they think and act.