It’s all about defining random. Uncertainty and unpredictability do not necessarily mean there is no pattern. In fact, there is little evidence that “patternlessness” can even be.
On the other hand, everything that seems regular could cease to exist the next instant, in a purely random event.
I believe that scientists have tried to come up with random number generators based on all sorts of properties such as Brownian motion, small fluctuations in heat or electricity in some sort of filament, etc.
But when some other scientist looked at one of these contraptions, they always found some pattern that made it not completely random.
So it might be that the universe is constructed in such a way that complete pure randomness is impossible.
And the fact that the universe is still here after what we believe to be billions of years of existence, might suggest that whatever patterns guide the universe, non-existence is not included.
Pure randomness would mean that we could never exclude the possibility that everything would end in the blink of an eye.
But if every quasi-random phenomenon has to have at least a smidgeon of a pattern to it, then it might be that there is no way to completely annihilate the universe.