You're paying people to do the role either way, if it's not dedicated staff then it's taking time away from your application developers so they can play the role of underqualified architects, sysadmins, security engineers.
Yeah, and nobody is looking at the other side of this. There just are not a lot of good DBA/sysop type who even want to work for some non-tech SMB. So this either gets outsourced to the cloud, or some junior dev or desktop support guy hacks it together. And then who knows if the backups are even working.
Fact is a lot of these companies are on the cloud because their internal IT was a total fail.
From experience (because I used to do this), it’s a lot less time than a self-hosted solution, once you’re factoring in the multiple services that need to be maintained.