It would be a task for sure but a really useful resource that could be built up over time. I think there could be a lot of folks who would contribute - and surely users would benefit from having a central source to start from and easily get to specific links by regions of interest.
So, a question and a possible suggestion:
The question is whether categories might be the best way to organize these on Wikitree since these seem to allow a common starting page - but also nested subsets, by region, country etc. (And in most cases these geographic categories are already established for other purposes).
A suggestion would be that maybe the geographic area projects could be reached out to in order to contribute core links on a sub-category page for their region. I'd be happy to be a point person for three projects that I'm currently involved with: France, Acadia and Québec.