Discrimination against all but protected classes (eg race, religion, et c) is not only legal but standard practice; when hiring SWEs you want to discriminate against the inexperienced, those bad at code, et c.
the point here is that not everyone goes through the same recruiting process because of these programs. also, coding interviews do not test if you are a good software engineer or computer scientist. they test how well you memorized optimal solutions to problems and how quickly you can reproduce them. they also discriminate against those with anxiety or other mental issues or those who have not recently graduated. and they do not test many important skills besides writing code.