In my opinion I think most governments in developed and strong states will not make bitcoin or crypto legal tender since it would result in them losing control over monetary policies. (except for japan..)

But I think crypto will become more accepted over the internet especially for e-commence. And I think this is more than good enough cos e-commence will become more and more prevalent than physical sales. So in the future we will use more and more crypto when we shop online and pay for services online but in the physical world when we buy a coffee, we will use fiat.

When I say fiat, it means digital fiat which can be form of govt-backed crypto too.