Your answers so far help highlight the fact that we have absolutely no idea. Essentially this is a metaphysical and philosophical question and scientists are not particularly good at philosophy.

There is nothing intrinsically or philosophically different about quantum mechanics that would suggest it isn't deterministic, despite the assertions that this somehow answers your question. There are theories that support a determinist universe and theories that don't, but demonstrating which represents our reality is not a simple matter.

As humans that believe in free will we naturally reject the notion of determinism. That only hinders our understanding of the universe, because a scientific approach needs neutrality.

Naturally, when a scientific model came along that emphasised probability, entanglement and observation many people latched onto that as rejection of determinism. This could be seen as an unhelpful bias.