>Some of them are templates which also need to be in the repositories.

Letting people who are editing templates use git seems perfectly fine to me. Using git to version constantly changing data is what I think isn't maintainable.

I think at some point that polluting the commit logs with data changes, dealing with merging issues, and training everyone who wants to change data on git imposes a hard limit on scaleability for this approach.

You may never hit that limit, but I don't think this would work for very large teams, and I suspect that if you git to the point that it stops working, it will be very difficult to sort it out.

I agree, the point here is to push off the cost of building the interfaces and making the data fully dynamic until they are actually needed, because we often find they aren't.

As for the commit pollution, I don't see this as much of a problem. In the long term we're always going to have lots of commits!