Which version of Adobe Acrobat Pro (allowing for creation of fillable forms) was the last to have a perpetual license, and is it compatible with Windows 11 Pro?
Adobe Acrobat 2020
Is that Pro or Pro DC?
For Adobe Acrobat DC you need a subscription.
DC is the version number of the subscription-based model. The perpetual license is called 2020, and it can be either Pro or Standard (Windows only). And yes, it's compatible with Windows 11. See:
Sorry for beating a dead horse, but just to confirm my understanding... Adobe Acrobat Pro 2020 will allow me to create fillable forms, correct?
You can create forms with Standard and Pro.