Fundamentally the best case scenario for attrition is immediately after the season. When a player leaves after signing day, Addazio doesn't have the chance to fill the spot before games begin. Essentially BC plays a man down, just like we did when banking scholarships. What's happening now is not the best case scenario, but it does have some benefit.
Losing players is not a good thing. Though not much was expected of Craan, Meredith or Ricci, all probably would have played this year. Now they won't and a thin team is left thinner. Plus you never know when things might click for a player. One or all of those three could have been this season's late bloomer. But we will never know this since all are gone. But the reason losing a player is still better than not bringing in a player, is the benefit it has on the team's culture.
When a new coach comes in he is trying to get guys to buy into his program. BC has a long road back and this season might be rough. If the team does struggle, you want every player around still believing. Still fighting. A guy who doesn't buy in yet hangs around might influence those guys on the fence about football or Addazio. If the recent departures didn't want to be here, BC was smart to encourage them to leave.
I don't blame the guys who left. College football can be a fruitless grind. It can be even worse if you are losing and no one believes in you. Playing without 85 scholarships is not ideal, but at least in Addazio's case it is about rebuilding and not mismanagement.