How much will the cap go up by the end of that deal? You know the Packers are factoring that in
How much will others players salaries go up as well? So you are going to dump or trade Cobb and Matthews to make room for Mack this year. He still will want to get paid next year and while the Packers are in better shape cap wise they do have their own free agents who will want a piece of that cap as well and if not they will need to get replaced.
looking at the Packers FA next year the highest paid ones this year are Matthews, Cobb, Wilkerson, Clinton-Dix, Lewis, Kendricks, Bell and House making over 1 million this year (around 37 million total) Most fans would probably say let every one of them go because they are not worth what they will make. OK so now you have to replace several starters and key backups. As long as you are fine with replacing them with cheap players then yeah all is good but if you would be hoping to get some mid to upper level talent to replace IMO them you are looking at paying the 8 replacements at least 37 million.
Then you have several players making less than 1 million who may be counted on to contribute and keeping them will cost quite a bit more than they are being paid (Kumerov, Byrd, Brice, Gilbert, Allison, Ryan) so that will eat into the cap even more.
I understand that the cap keeps going up but so do players salaries. It's not just the few guys who are making the big bucks its everyone. The more you pay just a few players the more critical it is to have good young players on cheap contracts contributing. Players like 2 first round draft picks. Trade them away for one of those guys taking a big piece of the cap and now not only do you have 1 more guy taking a bigger chunk of the cap you have two fewer young guys on cheap contracts who could contribute.
I get both sides of the argument and I would love a guy like Mack but I have said it before and so have many others. Mack for 2 first rounders? I could live with that. Mack for 20 million in cap hit? I could probably live with that. Mack for 2 first rounders and 20 million dollar cap hit? Thanks but I'll pass. Its just too expensive. I'd rather take that 20 million and look for a couple of 10 million dollar free agents next year to bolster a couple of positions and use the two first round picks myself. That's possibly 4 solid to very good players with the potential to be a lot more (yes the potential to be less is there but so is the potential for Mack to get hurt and we lose it all) vs 1 player who could get hurt . 4 for 1 I'll take the 4 even if the 1 is Mack.