Delta rejected adopting SpaceX's
@Starlink on its fleet because it wanted to provide internet connectivity to passengers via the Delta Sync portal, instead of the Starlink-branded portal. Delta has since chosen to partner with Amazon's LEO.
This will result in Delta falling behind many of its competitors in offering high-speed WiFi onboard, as many other carriers are already offering or installing Starlink, whereas Amazon's LEO airplane WiFi for Delta is still a couple year away (or more).
Satellites currently in orbit:
• SpaceX's Starlink: 10,400
• Amazon's LEO: 300
(Delta rejection info according to Ron Baron)