> and if you just let them install the app but then reveal that they can't actually run the models, they'll feel ripped off.

Just release some simple free "test application" that checks whether the computer satisfies the system requirements and does something "simple" (but relevant for the user) so that the users want to try out this simple free test application and want to update their hardware so that it can run.

Now, after the users have been incentivized to update their hardware so that they can run the cool test application, you can upsell your users to the "full software experience". :-)