Royalty free just means manufacturers don’t have to pay AMD a fee, it’s still proprietary meaning Nvidia isn’t allowed to use Freesync directly. Only the VESA standard adaptive sync is open source (on which Freesync is built), so they have to use that.
1440p Gaming Monitors will definitely have a lead over 1080p Gaming Monitor because of the higher resolution, comparatively cheaper pricing.
1440p vs 1080p
4k vs 1440p
The jump from 1080p to 1440p is definitely more noticeable than 165hz to 280hz