The pitching “has mostly held up” strikes me as pretty false- seeing how the team just went a month without a starter winning a game. They have the second worst ERA in the league.
I just ran through the month of July box scores to respond to this idea of the starters not winning a game in the month (until the last day). Sox starters had four games in July that they left in position to pick up a W, but the Red Sox either lost the game, or the bullpen lost the lead but the Sox later won. Another two games that the starter went 5 IP, gave up 0 or 1 runs, and left a tie game that the Sox later won. There was also a game that Crawford got the W, but Davis went 2 IP as an opener. So that's 7 games that could have been starter Ws that weren't. There were another 4 games that the starter (or opener/starter combined) provided a Quality Start® that the Sox lost by scoring just 1 run.
Your larger point -- second worst ERA in the league -- holds. But the "no wins for starters" thing is a red herring.
The idea of "the pitching holding up" relates back to Cesar Crespo's post, which seems to be referring to the prospects called up to fill in.
So specific to those prospects in July:
Winckowski had 3 good starts (6 IP/2 R , 6/3, 5/2) and 2 bad starts (5/6, 3/5)
Crawford had 5/5 good outings (5.1/0, 5/1, 6/3, 6/3, 5.2/1)
Bello was not effective in three starts (4/4, 4/5, 4/5), but did ok following an opener (4.1/2)
Seabold had one ok start (4/1) and one disaster (2.2/7) before getting hurt
Overall, the Sox got 10 good outings from that group and 7 bad outings. I'd call that a small success. (And we knew going into it that Bello wasn't going to be ready, as excited as we were to see what he could do.)