You're right, of course.
However, John Henry is still the best owner in Sox history. I don't know what key decisions he did or didn't make, but as a minimum he hired a front office who knew when to fire people and how to build a team that ended the 86 year "curse" and brought home 4 WS.
It now seems apparent that the hiring of Chaim Bloom 5 years ago signaled a sea change--as you say, a smaller team payroll. For most of JH's 20+ seasons as owner, the Sox were at or near the top. Now they're in the middle.
Meanwhile, the value of the Sox franchise keeps getting bigger and is currently $4.5B.
It's true that attendance at Fenway has dropped from about 3 million 15 years ago to 2.7 million last year, but guess what? The Yankees attendance, despite their continuing to spend big on players, has dropped from 3.7 million to 3.3 million over the same period. The Dodgers attendance has gone up from 3.7 million to 3.8 million.
And there's also the tiny, insignificant fact that last year the Orioles and Rays, with their infinitesimal team salaries, came in 1st and 2d in the toughest Division in MLB. And the Yankees finished 4th, just 4 games ahead of the Sox, and didn't make the playoffs.
Biggest payroll last year? Mets, who finished 75-87. Yankees were 2d biggest. 3d biggest were the Padres, who finished 82-80, also 4 games ahead of the Sox. 4th biggest, Rangers, won the WS. 5th biggest, Philly, made it to the NLCS, where they lost in 7 games to the Diamondbacks, whose payroll was 21st in MLB.
I'm not saying JH is right or wrong. I admit I wish we still had Mookie, but there are also plenty of examples of bringing in and keeping players who didn't earn their salaries.
Time will tell.