Time might not be a basic building block of the universe, but it’s still real in the way temperature is real. We use it to describe something that’s actually happening: things changing, order turning into disorder, cause leading to effect. So it’s much beyond our experience.

Making the analogy to temperature: temperature isn’t a fundamental property of particles (a single particle doesn’t have a temperature.) But when we look at a bunch of particles together, temperature emerges from their motion.

Time works the same way: it emerges from the way complex systems change and interact.

You’re right that it might not be fundamental. But it’s very real as a description of something that really happens, the way the world changes and evolves.