A possible downside to this to think about:
Everyone knows that WWE likes to micromanage things, and this tournament will probably not be anything different. Progress and RevPro are most likely counting on this hype resulting in some extra subs to their demand services, but what happens if the WWE decides that the qualifying matches cannot be aired unless it is on the WWE network? Technically it is WWE matches so they should have some type of claim.
And from the talent perspective, WWE is going to sign these guys to temporary contracts for legal reasons, which means they are going to be able to determine what independent work these guys can then do for a while. Before you say they cannot, let me point out that they do this. Every inductee into the Hall of Fame who is not working for the company signs a temporary contract upon agreeing to be inducted which stretches up to six months after induction, and during that period WWE has legal right to null any appearances that person has booked/planned at say conventions. This is so they can protect their image by not having a hall of famer show up the week after induction at some flea market in bummfuck Indiana. Odds are that talent brought in for this tournament end up having to sign similar deals to participate in the tournament. And a lot of those guys rely on hustling from show to show to make ends meet. Notice how Gargano and Ciampa, who are NXT regulars aren't working as many smaller independents now, but rather only the big ones and international tours. Is every guy brought in for this tournament going to have that same luxury?
There's a whole lot of good faith shown towards WWE here to do these guys right.