It's always better to be safe than sorry. Many Software devs can be trusted to not do anything too stupid with their machines, but every person has blind spots and can be tricked. At the company I work at, the IT system is pretty permissive at what can and can't be done, but the Admins do block installing programs that ask for too many permissions under the hood (like some custom drivers and things that want console access) or that simply aren't allowed due to company policy (i.e. Postman, because it just sends too much information to the cloud). Even a well-meaning dev usually isn't aware of all the details of a program they want to install or the company policies - there are too many to reasonably know at all times. So it's easier to block stuff, and if someone really does need something they just ask and get it unblocked for themselves.
You can also never be sure that a dev isn't doing anything malicious. Of course that's rare, but when it happens the damage to all company projects is just too large.
It's also not much of a hierarchy thing, the Admins are on exactly the same level as devs, their job is just a bit different.
I don't think your ban reason leaves a lot of room for that..