I'm just not sure why?
Minotaur's are +3 ECL According to the wiki (I'm pretty sure someone updated it, so that's good)
But the Wiki still states that picking the Minotaur Mystic bloodline, gives a +1 ECL
Though I'm not sure.. why?
You lose 2 str and 2 dex, to make up for the 4 Wisdom you gain, so the exchange is completely even. It's still the same +6 / -4 attribute adjustment with no further changes.
Is this just out of date on the wiki? I'd assume not since it got updated to reflect them no longer having spring attack and their ECL being adjusted.