Yes, standard interview loops also discriminate, and the more time they take, the more discriminatory they are. Any on-site requirements compound the issues.
Like Yegge says: provisional employment/internships solve all of these issues. You get the best of all worlds: stable employment for the candidate where they get paid a regular wage and aren't under a stressful interview setting, and lots and lots of work samples for you, the employer. It's not perfect. For example, it can be difficult to entrust the provisional employee/intern with anything impactful if you don't know whether they'll be employed at the end. But it is significantly better than the alternatives in most contexts.