I think you missed his math. Yes, you get 6%, but you can't just ignore the $95 annual fee when you're trying to determine its value compared to the non-free version of the card. Take for example, this scenario: you spend $2,000 in grocery stores in a year.
With the Blue Cash Everyday, you earn 3% on those groceries, but no annual fee, so at the end of the day, you get $60 back.
With the Blue Cash Preferred, you earn 6% on those groceries, but with a $95 annual fee, so at the end of the day, you wind up only $35 ahead ($120 cash back, but less the $95 annual fee).
So a BCE card would be the better choice, since your BCP would have only gotten you ~1.5% cash back after you take into account the annual fee.