the nostr protocol has problems like this also... lists, for example, these things can get enormous and have a problem of sometimes disappearing because of funny relay and client implementations - it's my view that the solution there would be to add a CRDT type for list edits, and presumably ones that support it will also have caching so the bandwidth problem is solved for users who care and client devs who care
the same will happen eventually with email
email is a dead end, it is controlled by like 5 companies now and a defcon 1 data leak is just a matter of time, and a secure, encrypted alternative will become desirable to users
most companies already have a presence on X that they use for customer support, it is not a hard task if enough users for a service are on nostr and getting these companies to pick it up