I thought all NFL blackouts were suspended?
NFL continues suspension of TV blackout rule
There are two types of television blackouts: one for when a game does not sell out, and another for when the game
does sell out. I believe PtPF was referring to the latter.
The more well known one is the type referred to in the link, when a game does not sell out. That one, as noted, was suspended in 2015 by league owners.
The second type of blackout is not as well known but is still utilized by the NFL: for when a game does sell out. When that happens the game is available on local TV, since all tickets have been sold. In that scenario no other game can be televised at the same time.
The idea was that the NFL owners wanted to limit the number of no-shows. If a team had a precipitous drop in performance some fans would rather eat the price of a ticket and watch a better game on tv, especially later in the season. Getting you to pay for a ticket wasn't enough after all. The owners were still counting on you to come in and pay for parking, beer, soda, water, food, a yearbook, hat, t-shirt, etc.
Normally Philadelphia, Tampa and Minneapolis would receive no early AFC game (blacked out) because those teams are playing at home at the same time as the Pats-Miami game. Not the case for week 17 (and if there is ever a similar situation in the playoffs).