We're discussing a hypothetical situation where SHA-1 gets even more broken. From my original comment in this thread (https://news.ycombinator.com/item?id=49924179#49925367):

> If I can forge commits with any SHA1 hash at will

We probably don't want to wait until there are practical pre-image attacks discovered to change away from SHA-1.

This is a fair point.

I think I stand by my second proposal. I also think it's absurd that, after all these years, upstream git still can't figure out a credible migration plan.