The bad news is that you are stuck with it. This screen is not one that is user created or changable and does not appear in the "Data Screens" configuration section of your activity profile. Garmin believes you need it so that's it, even though all the fields could have been configured on a data screen if that;s what you wanted. The compulsory screen appears as the first in the screen cycle whenever you are using the smart trained.
The specific field ie "Resistance" is actually a data field in the "Smart Trainer" category of fields and is called "Trainer Controls", it defaults to Grade, Resistance or Power depending on which you selected for the workout.
And further to the bad news, since 18.23 someone in Garmin has decided you also need and other screen that you did not ask for whenever you are also doing a "follow course" on the Indoor profile, again all the fields could have been configured by the user if they wanted
Good to know that Garmin knows better than its users what they need?