why there is no option to delete sms in marketing cloud, whereas we can delete journeys, emailers, data extensions etc. on the other hand.
2 Answers
This is more of a product design question, though I agree it's not very userfriendly.
Anyway, you should always mark the SMS messages that are not in use / expired as Inactive in MobileConnect, as this way they will at least get removed from the view in 6 months time.
So while you cannot delete them manually, the documentation states the following:
After 180 days, MobileConnect archives inactive messages and removes them from view. You can still review information on archived messages in the calendar on the day the message was sent.
You can delete the SMS message, which is in DRAFT status simply by selecting a different template. The popup will tell you that "changing the template will discard the draft". And eventually, the message will be deleted.