To me, the owner's responsibilities are:
1. Hire the right staff (executives) who will make the right baseball decisions. Get the right leadership in place.
2. Give the baseball staff the resources ($$, namely) and autonomy to make the right decisions. Let the leadership do their jobs.
To me JR has failed in these regards. The constant "promote within the family" mentality undercuts objective #1.
Objective #2 you can make maybe make an argument for, but the fact is:
This team is being out-contract-spent by the Twins
The Twins have now committed 9-figure deals to 3 players I think of off the top of my head (Mauer, Buxton, and now Correa), whereas the Sox's largest contract is $75MM
JR has shown to insert himself into lower-level decisions to undercut his own executive staff
Hiring of a manager
Refusing to pay top dollar for pitching after shelling out for Jaime Navarro
The results are that, in 41 years of owning the team, he's brought home 1 World Series championship. He's brought home 1 AL pennant. If it weren't for literally lucking into the greatest basketball player who ever played, he'd have 1 championship in 78 combined years of sports ownership.