A university degree tells me three things a Coursera certificate doesn't:
1. A graduate have more breadth and depth in a given major. Standford's CS course includes math, physics, engineering, programming theory, data structures, algorithms, etc. (Just picked Stanford's program at random, not advocating they're perfect)
2. A graduate has exposure to multiple topics/subjects, and hopefully has some critical thinking skills. A Coursera cert doesn't do that.
3. Somebody graded them. It wasn't some massive online system.
Maybe other people don't care about these things, but as a former manager, I've found these qualities produce a better well rounded individual in the workplace. There are exceptions to the rule, of course, but that's my experience.
To your point: All these things can be replaced, but I'd argue micro-degrees don't do that.
I do hope this is solved: The price is crazy.