If the arrest record is warranted, I fail to see your point. The outcome of not having a record when you probably should have one is probably net worse for society, given it won't show up later on a background check, for example.

It’s the same point as - if a person needs to be committed they should be. We are in this position because cops have not been shown to be fully trustworthy in a lot of these situations. It is infinitely better to not have the cops involved at all unless they are absolutely needed at which point the medical care workers can send for them. This new way is a win-win for everyone involved.