I am sure it was put in place for "competitive balance" purposes. Same with limiting IR/ practice squads etc... So deep teams can't just stash players and thus the use of the waiver system, allowing the worst teams to get first crack at released players.
I remember years ago the Rams and Redskins were two teams that would put 20 guys on IR and then just activate them when you needed them Especially linemen. They also used the "Taxi Squad" to its fullest. There was no FA so teams used that as a way of developing players.
So now you can't do that and they make the good teams get rid of guys that will certainly help bad teams.
So they are essentially penalizing good front offices who do their job and get better, by finding top UDFA's etc... and "spreading that wealth" so to speak to those who do a poor job and don't put the time in or are simply inept at building a team.
When you think about it, Bernie Sanders should run for NFL commish if his other interests don't work out for him.