Minors and hotfixes allow you to release a new version for an older release (like if you released 3.7 but you found a bug present in 3.4, you can release 3.4.1 which would be newer than 3.7), making it possible to have multiple supported versions at the same time.
The name "serverless" doesn't mean that there are no servers. It means that, as a developer, you don't need to manage the server. It's abstracted out for you.
I know what it means, I pitched serverless as a new tool to a former employer back nearly a decade ago, I had to thoroughly research it because the manager would of said no if I had no idea how it worked, funnily enough, he said yes before I could finish my entire pitch.
Minors and hotfixes allow you to release a new version for an older release (like if you released 3.7 but you found a bug present in 3.4, you can release 3.4.1 which would be newer than 3.7), making it possible to have multiple supported versions at the same time.