Matt (and Acqua,) I am not the expert about your question, but I can provide some perspectives.
In the mdl_course table, every course has to have a unique primary key, which is the "id" field. This is the number that displays in the URL, as Acqua shows in the original post. For quite a while, it seemed to be a sequential number starting with "1." A primary key needs to be unique, so the database assigns this number. Somewhere along the way, perhaps in 2019, this number (in my Moodle) switched to a larger number, 31460. Then in 2021, it switched to an even larger number, 47665. Why? Don't know. My guess is that this number might be somehow associated with the Moodle version number, and it might be used to help diagnose which Moodle version created a course. Since this is an arbitrary primary key number, it has never bothered me. However, to answer your question, no, one (Acqua) doesn't have control over it.
That being said, there is a textbox called "Course ID number" that you will see when editing course information. In my Moodle, this is blank by default. It appears that this is the field that schools have control over, and schools might want to coordinate this Course ID number with other school systems. For me, no, no need to do any coordination. However, I have personally decided to make this "Course ID number" relate to my sequence of courses by using my own code. For example, a code of 310. What this means to me is that this course was created in Moodle 3.x, and it is the 10th course that I have offered. Note, I run my own Moodle for my own purposes, so I can do whatever I want. I have courses going back to 125, 232, etc. Yep, 232 was my 32nd course while using Moodle 2.0. Someday, I will have a code of 401.
This "Course ID number" is the "idnumber" field in the mdl_course table. Sometimes I will create SQL
queries and use this idnumber to sort by course. This might be where Acqua is heading.
Well, hopefully, something that I have said will make sense to you and help solve Acqua's problem.