Change license of contributions on this forum?

Sarven proposed (IIUC) to change the license of contributions to this forum from CC NC-SA 3.0 to CC-BY 4.0.

I think the version update from 3.0 to 4.0 should be OK, but I don’t think it’s possible to remove the ‘share-alike’ and ‘non-commercial’ clauses from previous contributions. We could maybe use a more permissive license for new forum contributions going forward though?

What do other people think?