It's tied directly to the remotely managed account, that's how the account works. If you don't sign into the account, the software won't be installed.

Students don't get to decide what software to install when it comes to logging in to school accounts. Generally the laptops are provided by the district, but it seems OP was trying to add another personal device to their system.

You can't participate in their system without the software. So I guess the alternative would be to block personal devices from logging in like this at all.