There's a bunch of people who are "members" of the vim organisation on GitHub. I don't know if they have full admin privileges or just commit/issue access. I never really understood why this has to be a problem in the first place: can always clone the repo and continue working on it if Bram disappears.
vim/vim is licensed under the Vim License
There are no restrictions on using or distributing an unmodified copy of the software. Parts of the software may also be distributed, but the license text must always be included. For modified versions a few restrictions apply. The license is GPL compatible, you may compile the software with GPL libraries and distribute it.
Source, if anyone wants to dig deeper: https://www.gnu.org/licenses/vim-license.txt
Unsure why I'm being downvoted but okay.