My take is that if it selects against candidates who view remote employment as just another free lance job, more the better for both sides. Remote employment is not another form of freelance work. The relationship is different.
I'm not really sure how you've made that leap. It doesn't seem to me that hiring people for a freelance job selects for people who don't think of remote work as a freelance job. If anything you're selecting for people able to make that commitment.
If the company is guarding against false positives in hiring, then what they are looking for is people who are able to reframe the short term form in terms of the long term form. That is people who treat the trial as trial employment rather than as strictly a free lance proposition because people who have made that transition are a safer bet than people who at the end of a month are still thinking like free lancers.
Putting on a suit and tie for two days of travel and job interviews is just as much a mock business situation as a trial project. It's just likely to be less informative to both parties. And it's still selecting for commitment to the hiring process.
The only point at which this becomes a problem is if the industry expectation shifts so that you can only find a good job by performing contract work for a month before knowing if you'll be hired or not.
As long as there are options, well... the people who prefer doing algorithmic puzzles will interview at the puzzle-interview companies, the people who prefer doing side-projects will interview at the contractor-then-employee companies, and so on and so forth...