Until 2010 I worked for Route Messaging (now they are called Telesign) on internal systems as well as integrations with mobile operators and other "messaging brokers" around the world.
MMS was indeed order of magnitude more expensive than SMS and several orders of magnitude less used.
Reasoning for such high prices was more about mobile internet/data back then being really expensive "1G" - and MMS was (still is I guess) using mobile data to send/receive "multimedia messages".
At this point I expect that cost of MMS is more about maintaining legacy systems/servers for that.
Although in something like 2008/2009 integrating through legacy SMS protocols (those previously used by beepers/pagers) was cheaper than through modern protocols. Some operators had hardware boxes supporting those that were already paid off long time ago.
MMS was indeed order of magnitude more expensive than SMS and several orders of magnitude less used.
Reasoning for such high prices was more about mobile internet/data back then being really expensive "1G" - and MMS was (still is I guess) using mobile data to send/receive "multimedia messages".
At this point I expect that cost of MMS is more about maintaining legacy systems/servers for that.
Although in something like 2008/2009 integrating through legacy SMS protocols (those previously used by beepers/pagers) was cheaper than through modern protocols. Some operators had hardware boxes supporting those that were already paid off long time ago.