Let's talk about the Phoenix Suns Phoenix is the 14th largest metropolis in the country (when including surrounding areas covered by the same TV networks; Dallas is 4th, by the way), placing them right in the middle of the 30 NBA teams in terms of market size.
The Phoenix market compares more to San Antonio, Detroit and Minnesota than Dallas and LA. Robert Sarver spent a boatload on the Suns just 7 years ago and likely has not seen a healthy profit in any year since 2004-2005 when the Suns took the league by storm on the back of a relatively low payroll.
Sarver is one of the "young" owners who haven't seen the return they'd hoped for, but don't pretend that he's alone. Without better revenue sharing, the system is skewed toward the bigger markets being able to afford the highest payrolls year over year. The only penalty a team will incur for over-paying is the dollar-for-dollar "luxury" tax. Yet when the big markets make 5 times more money on local revenue (ie. on top of ticket sales), they can more than afford that penalty.