I don’t think there’s any universe where a company runs an international chain of retail outlets in order to support a free email service. If that were the standard, free email providers just wouldn’t exist outside of bundles with other services.
We treat email almost as we used to treat postal mail: we expect it to be available to all ("digital transition" replacing human-fronted public services with digital one).
If we treat it as a utility, it's fine to regulate it as such. If <big corp> want to make money, directly or indirectly, by offering email service, they should have some standard of service. If they can't we can just make it public service, which wouldn't let <big corp> make money out of it, but would also guarantee it's available to all.
Either way, eating the cake and leaving it whole, like it is now, shouldn't be an option.
