But isn't that the way freelancing works (should) by default?

On the employee side, at least regarding engineering, the biggest problem the freelancing sector has been facing are pervasive fake job posts. It has come to the point of making Upwork unusable, you simply know that a job post is fake. My statistics are a pristine 100% in a 3 year period, it's insane. Despite very positive reviews and a great start, I have not been able to land a single job in 3 years there, in despite of permanent effort and being very cautious respect to where I send a proposal. Yet, nothing. Making fake job posts seems to be more profitable than requesting actual work.

I thank god don't depend on that, so I can take my time, read the post, investigate the source, write a thoughtful letter, etc. So it's not that I'm desperate, shoot blindly, lack strategy, etc. I had actually a great start at first. Now it has winded down to non-existence, all jobs are fakes. It's surreal.

That tendency of degenerative behaviour in the employer side is the leading reason good talent is nearly absent from those platforms nowadays, so naturally only workers of lower quality tend to remain.