If CLIs are designed around facilitating the easiest means of editing the most commonly-edited word, different programs will end up with semantically very different CLIs. In some programs, the "noun" (e.g. file path) will be the thing most frequently edited. In some others, like systemctl, it'll be the "verb", like start/stop. That means that different programs designed around this principle will be semantically extremely inconsistent with each other.
On the other hand, if consistency of "base_command sub_command --subcommand-arg sub_sub_command --option argument" is taken as the guiding principle, many different tools will act semantically similarly. This enables unfamiliar users (talking first-time users or people who have just opened the manpage for the first time) to intuit the right way to present commands to those tools, rather than expecting them to memorize (or re-look-up as needed) each one's specific semantics.
While there's merit to both, I think the second one--systemd's CLI approach--is better. Put another way: the user-centric and consistent (with other applications) design are sometimes at odds in this way. A tool that is hyper-focused on optimizing the most common tasks for its (power) users risks oddball status and hostility to new users. It's important to pick a point on the spectrum that appropriately balances those two concerns. Python ("There should be one-- and preferably only one --obvious way to do it") and the Apple HIG ecosystem both understand the truth of this: that it is sometimes necessary to trade away efficiency for familiarity/consistency. There's a reason Perl languished while Python grew.
Like, I get it. I've been a sysadmin/devops for decades, and the paper cuts add up. But it's easy to forget the paper cuts I'm not getting: modern tools are (generally, with exceptions) more consistent; there are fewer commands that are resistant to memorization and need to be looked up each time; fewer commands that lead to questions like "wait, is it 'cmd help subcommand', 'cmd --help subcommand', or 'cmd subcommand --help'? Am I going to have to Google how to get the help output of this command?"