As described in the "Battlefield 6 Maps, Modes & Portal" trailer (at 3:20) Verified Portal Experiences are supposed to have "full progression and XP gain".
This was true until earlier today, it is currently not true anymore. Only "Match Completion Bonus" seems to be active on Verified Portal Experiences. The "Win Bonus", "Score", "Accolades" is disabled. The four secondary progressions "Mastery XP", "Daily Missions", "Assignments" and "Other Challenges" are also disabled.
I assume this is a bug on your part.
Unfortunately its not a bug and DICE/EA decided to gut the Xp earn rate because people were making xp farms, which in turn leaves players like me who like to play vanilla experiences with bot backfill enabled on the curb, hopefully they fix this because this is really annoying
