I'm writing from personal experience in a middle of the table public school, with a single IT guy helping out around 1000 pupils, who regularly get their computers locked with said MDM.
It's possible other school districts with a less diligent, but similarly overworked, IT guy just give up and don't even hand out the computers anymore, especially if they don't have enough of them, after being on their second or third kid.
Those are certainly above 6 grade, because I am aware of few schools, whose desktop computers, with luck get to a have a visit from some local computer store, on demand after lots back and forth with the regional ministerium office regarding how it gets paid.
None of them has hardly an IT guy, or girl on site, and as usual "em casa de ferreiro espeto de pau", acquaitances have been invited to have a look at their computers.
The IT guy is the TIC professor, who does it in excess of work. The guy is the son of the former TIC professor. And of course, I was roped in to help for my kids’ classes.
And yes, it includes kids from at least 2nd grade. My COVID kids got their laptop on 1st grade, but that's no longer the case.