Apple has shown a warning on downloaded-from-the-internet apps since Mac OS X Tiger. That's the only reason it's being shown, there is no scary warning that users need to step-through in some basement in System Settings as they would for a non-notarized app. The popup even says "Apple has checked this application for malware". It is the smallest of friction present to get apps to run, as I'd argue that the sandboxing requirement for App Store apps and the need for a sign-in make the App Store a worse experience.
And I say this as someone more or less utterly in the same boat as you. I bought a used Thinkpad last June after seeing the first Tahoe beta. It's clear Apple is not the platform for us anymore.