My SBC storage was stacked with low rated players as I've been struggling tonget anything above an 85, so I'm sort of glad they did something. I'm basically out of bronze players to use, there is no way I'm shipping 750 coins at a time to get 3 bronze players so the grind is basically over. If they wanted to do it right they should have included more daily bronze packs.
You are right though, it definitely should have been a better SBC that they put in, personally I would of preferred 81+ double upgrade packs or player picks. They may be slightly more expensive in terms of players, but at least I get a decent chance of getting something usable in other SBCs.
It's all about driving people towards the store though, I've got 10 days to get four 88 rated squads and two 87 rated into the Mbappe SBC. Today I've opened around 75 players picks, 18 grassroots grinds, and the 3 84+ x 5 packs along with some of the objective packs available. The only things I got of any use were, one 91 rated, one 88, and 2 87 rated players. I'm not listening to any EA community manager or EA defender say that's just the probabilities in packs at work because it's bull to be honest. One of my 84+ × 5 packs was a full 84 rated duplicate fest.