I think the arguments is there is no way to validate it was you that did the work. There's been too many instances of groups that do interviews for others or the work for take homes to help get people placed. There was a big deal about some H1Bs a while back where the people that showed up didn't look anything like the people that interviewed. So I understand both sides.

It's frustrating though when you've done a lot of work, as you've listed. I think in a good interview maybe going over that code and getting the chance to explain things you did, why you did, or issues you had, could also go a long way.

Interviewing is tough, more so at scale.