In the company I work for, there is a team that has isolated itself to some extent from other teams and works at a furious pace to keep their particular section of the business happy. We're lucky enough that they spun up their own repo to do their work on, so they don't actually impact other teams, but if the quality of the commit messages is anything to go by, I am 100% certain they're going to end up in a huge mess, if they aren't already. The team lead encourages this, and certainly doesn't care about commit messages etc.
Developers who care about other developers tend to write better quality code, because they care what other developers think of them. If you care about other developers, you will most likely write decent quality commit messages too.
I have seen over many years the types of developers who only care about moving their own code into production as fast as possible and getting to the next thing. There is a very high correlation with a mess at the end, which they inevitably won't have to tidy up because they'll be doing the next thing. These types of developers hate owning stuff in production, so they don't do it, so they don't actually care how maintainable their "clever" code is. I am very certain that a number of people reading this will be those types of developers.
As a manager, one of the first things I do is make sure that the PR titles (the PR text becomes the commit messages in squash-merging workflows) at minimum begin with a ticket number. Then we can later read both the intention and the commentary on it.
You're thinking like someone with a mature understanding of version control. Plenty of developers seem set on going their whole careers using git like beginners.
Personally no, the code is the "truth". If I need more I'm going to open a dialog with the author, not spend time trying to interpret a 7 word commit message, "good" or otherwise.
And for old enough code, the author may not be available, or more likely doesn't remember.
It feels like we're trying really hard to stretch the utility of commit messages here...
I don't feel that is an accurate statement for any complex system.
To the point of other commenters however, I wouldn't lay something this micro at the foot of the CTO in all but the smallest of organizations.