I just checked with the current release candidate of 2.22 (2.22dev7 which could be installed via ppa:privacyidea/privacyidea-dev - see privacyIDEA 2.22 prerelease).
Sending SMS works fine via SMTP provider. The token might have an entry
sms.Provider: privacyidea.lib.smsprovider.Ht...
which is a remnant of the depricated SMS configuration. But it does not matter. The SMS is still sent via the configured SMS-Gateway in Config->Token->SMS.