I totally feel you. Granted, this was implemented well over a decade ago. I'm pretty sure it even predates G code...
Thankfully it's automatically collected and not surfaced anywhere important. The Experience Cloud Debugger extension doesn't show it anywhere in an image request since it's just one of those things that just works behind the scenes.
But still - I do share a similar opinion. When I first found out about image request query string dates being 0 for January, I could not figure out for the life of me why they did that.
The first answers mentions that's it's simply a mess, but the second answer provides some pretty solid logic in that it's a lot easier to calculate month differences using the % operator.