Regional, yes, but not to any particular region. This has the potential to apply to "regions" all over the world, but not be limited to any particular one. At the same time, this question only applies to the regions indicated.
This would also apply to the questions about transit systems that allow bikes.
Do we need a new tag for these?
A tag like 'potentially-local' seems a little ridiculous, but I think I understand what you mean.
I think that the rides question might be better split up into a set of more localised questions - by country, perhaps - but there is a subset of users who don't feel that that kind of question is suitable for this site if it's to be generally and internationally useful.
The transit systems is as much about comparing the systems than getting any recommendations for places to visit to purely experience mass transit nirvana, so I think it's fine without a new tag.
