It is VERY obvious you know very little about the cap. First, of the major sports in this country the NFL is THE ONLY sport to have a HARD salary cap. Every team as a number that player contracts can not be over, PERIOD. Where you come up with a soft salary cap in the NFL is beyond understanding. Second, there have been several years where the cap has risen only slightly by just a few million dollars and in those years the Cowboys dead money was as large or larger than the increase in the cap so no the dead money doesn't always get absorbed by cap increases. Third, if dead money was just an illusion or just an excuse to use for fans then why doesn't EVERY team just renegotiate many contracts or half of their contracts so they can just go out and over pay for free agents knowing that next year they will just restructure those contracts, adding more and more dead money every year? Why - because the Cowboys who when the cap started were in cap hell from the getgo and continued for over 2 decades BECAUSE of dead money and very severely limiting what money they had to work with. Even grade school kids can figure this out.
First off, you've been dogpiled countless times in your short time here, so you might want to feel your way into this a little better.
If a team can be over the cap, then restructure an existing contract and suddenly be under the cap, then that's not a hard cap. There is literally no limit to the number of times you can do this, and when owners finally get tired of spending money on salary, they suddenly fall back on the very weak excuse of "We're cap challenged! We can't do anything!" The Commanders bought a million high-priced free agents this way to no avail.
Mike Fisher has explained this many, many times. The salary cap is a myth. Do your own research.
I'm not interested in teaching you football.