What you said is mostly true but there are also frequencies that ham operators can transmit in, but only have secondary priority to other uses.
For example hams can only transmit in the 1.25 meter band if they don't interfere with other users like the Automated Maritime Telecommunications Systems (AMTS).
For example hams can only transmit in the 1.25 meter band if they don't interfere with other users like the Automated Maritime Telecommunications Systems (AMTS).
https://hamradioprepper.com/us-amateur-radio-bands/