You don't need services when you can just use tools.

Is Morse code less useful because of the lack of viable Morse code service providers?

You're once again absolutely right! You can use tools without service providers.

You can use Morse code without any service providers whatsoever! Though using it to send messages solely to yourself might not be the best of all possible uses, it's absolutely a viable use.

Similarly, you could implement SMTP for yourself on paper. It might not be quite what was intended or maximally useful, but it's certainly a use. Some people might opine that it's far more useful with services implementing it widely and making its benefits available to many. I can't say they're being wildly unreasonable.