I don't think that expecting prospective developers to spend lots of unpaid time on a skill that's ultimately not going to be useful to the vast majority of them should be normalized.

Do you expect medical doctors to do an unpaid "trial" surgery as part of their interview? Do you expect lawyers to litigate a case for free before they'll be considered for a job?

As far as I know software engineering is the only field where in addition to experience & education you have to waste time gaming the interview process. Every other field seems to get away just fine hiring based on experience and/or education.