Because it's not a subscription i guess. Sync Ultra is the subscription, ad-free sync is just a Single In-app buy to not have ads in the app.

The difference between no-ads and Ultra is some online perks related to the use of the client.

Notification LED's, a REAL proximity sensor (not just the Selfie Camera), the headphone jack, a dedicated Fingerprint Sensor (because under display sensors are still bad).

I missed the iR blaster so bad in my phone that i ended up buying a USB-C IR Dongle in Aliexpress, and i carry it over in my keychain. The need to turn on projectors, AC's or simply turn off TVs in Shopping malls or Stations was so much to justify the purchase.