I'd be surprised if this stood up to statistical scrutiny. Yeah, anecdotally he lets guys go over 100 here and there, and like any manager sticks with a starter too long at times (though that's a lot less common in the current relief era). Pitch counts don't mean anything. Arguably they never have, except in extreme cases. But now the team is dealing with a dozen different more granular data points in any given game (including actual pitches thrown, high or low stress innings, and what both the velocity and mechanics say about their fatigue).
And yeah I think the Phillies have been lucky in how healthy the rotation has been, not cursed. And for three years now, too.
Plus, let's face it, Walker is only barely hurt. While Turnbull has never historically not been.
Allard was considered as legit a contender as Turnbull to be the #6 going in, and started the season as the 7. Then he stunk.
I think those high numbers aren't just injuries, but not having enough pitchers in general. Whether that's a guy like Walker failing or prospects who aren't ready (like the Dodgers pitcher the Phillies lit up).