Those multipliers will only apply if you are currently on an annual subscription (and only until your renewal comes up or you cancel). So I assume they simply want to make it as unattractive as possible to get most people to cancel it and move to the token based system.

That's not an answer. It's specifically a discrepancy between 5.4 and 5.4-mini. If you look at all other models/generations you see that the cheaper model indeed has a lower multiplier. It's very strange that only 5.4 doesn't have this.