Well, look, even if you're not milking quite as big a fraction of value out of the cost-controlled years as you do in the NFL (or to a lesser extent, MLB), it's still a factor - you still need both overall production as well as good value in order to maximum the production on your roster. You have to look at it through a value lens. How much of Golden State's pre-Durant success was from getting on-court production before they had to pay top value for that production?
2013-14: Bogut and David Lee at $14 each, Iguodala at $13. Steph (PER 24.1, WS 13.4, +15.1 on-off per 100) at $10, Klay (14.3, 6.7, +15.5) at $2.3, Dray (12.7, 4.5, -0.1 but +27.6 in playoffs) at $900k. Team went 51-31, lost in 7 to Clips in first round. Lee (19.1, 7.6, +11.2) was an impact player.
2014-15: Bogut $13, Lee at $15, Iguodala $12.3. Steph (28.0, 15.7, +18.1) takes his first MVP while making $10.6, Klay (20.8, 8.8, +12.3) is now a monster too for only $3.1, and Dray (16.4, 8.5, +14.6) shot up to star status while still making $915k. Team went 67-15 and pretty much romped to a title without ever facing a serious threat.
2015-16: Lee is gone, Bogut still at $12, Iguodala $11.7. Steph (31.5, 17.9, +22.6) repeats as MVP while still making $11.4, Klay (18.6, 8.0, +12.7) gets
kinda paid and goes to $15.5, as does Dray (19.3, 11.1, +26.3) who at $14.3 is still massively underpaid. With a rotation rounded out by a young but capable Harrison Barnes and Livingston, they roll of course to 73-9 and a famous, shocking Game 7 loss in the Finals.
2016-17: They sign Durant for $26.5M because of the huge cap jump, but two-time-defending-MVP Steph Curry was still at $12.1 and everyone else important only had their annual 8% raises. They go 16-1 in the playoffs, enough said.
I mean it's impossible to look at that and not conclude that the run was both enabled by superstar performances getting paid rotation dollars, and also sustained and extended (them signing Durant, repeating as champs, then going to the Finals in 2018 again) by that same brilliance-or-good-fortune in cap management.
Even dealing with RFA contracts like Smart and Brown, before you start risking a supermax on any of your all-stars, seems like a fraught endeavor. Where are those superstars getting paid a fraction of their true worth going to come from? We can keep Tatum at 1st-contract dollars this year and next, but he (and Jaylen) got too good too fast for us to give them "Steph and Klay and Dray 2nd contract" dollars, i.e. 24yo Steph signing 4/$44 in 2012 (partly due to health worries), 24yo Klay signing 4/$70 in 2014, and 25yo Draymond signing 5/$82 in 2015. But for every bargain like those (or Marcus Smart), you've got tons of situations where either:
(A) the guy you hoped would become a star maybe performs adequately to his signed value, but doesn't shoot up and give you huge excess value, or
(B) the guy you're sure is going to be a star proves it before payment is due, and ends up getting maxed or nearly so with his 2nd contract
Maybe threading that needle is just luck, I don't know, but it's what I worry about. Hence looking at Ingram and seeing excess value today but probably market value tomorrow.