Hope you don’t mind me bumping this with another +1, as a custom parameter as described above would be an incredibly helpful feature. I’ve encountered this issue multiple times and it’s always reported by QA processes. Thank you for considering!
Hi, I haven’t tested with transformed components, but doesn’t running a Remove Nested Components filter work? I wrote one you can also add as a prefilter for static instances.
My solution for variable fonts is running the filter on all layers before export on a duplicate file (best integrated into your own export plugin).
Looking at the code again I see there might be some limitations with nested components in special layer glyphs, as well as with atypical multiple-master setups. Use at your own risk (and please report any issues it might have with your setup).