I use VS Code with the Python extention regularly. Randomly this week when I try to enter debug mode via the usual approach, VS Code starts Powershell instead of the Windows Console like normal. This then fails. I've check and changed my default terminal setting, uninstalled and reinstalled the python extension, nothing is working. It's deeply frustrating!
The one potential thing I've done recently that might have impacted this is I used the remote extension to remote into several Azure VMs and work in linux there. The behavior may have started around that time (unsure) but I've scoured forums and the settings to no avail. Any idea what might cause this!?
I've just met the same problem, also when trying to run a python file via terminal. Happened since the last VS-Code update (August 2021). My default terminal is bash but somehow PowerShell was opened. I even tried removing the built-in terminal profile for PowerShell but it didn't work.
What did work: Downgrading the VS-Code version to July 2021 (version 1.59).
Detailed explanation how to downgrade: https://newbedev.com/how-to-downgrade-vscode