Hey StudentAdmin
indeed yes powerShell is a powerful and widely used tool for Windows Server administration, obviously as you asked it's not the only option available. Disabling PowerShell entirely might be an extreme measure, but lemme share you a few alternative methods for Windows Server administration. Classic Command Prompt (cmd.exe) is still hanging around for basic stuff, though it's not as fancy as PowerShell. Then there's the Remote Server Administration Tools (RSAT), letting admins manage servers remotely from a Windows client.
For servers without a GUI, you've got Server Core or Minimal Server Interface installations. They're a bit more command-line-heavy, but they get the job done. Task Scheduler can lend a hand in automating tasks, too.
I'm saying this again disabling PowerShell might seem like a tough, that's an awesome question hope you find the ans useful.
If this helps kindly accept the answer thanks much.