Looney entered the league as a 19 year-old baby, and I suspect those measurements reflect that. He's gotten significantly bigger and stronger in the intervening three years. I don't think Theis or Morris has Looney's 7'-4" wingspan or 9'-2" standing reach, and Morris in particular does not remotely anchor the defense or defend the rim like Looney (1.9 blocks per 36, career). At his current age, I think Looney's very close in terms of size, physicality, and defense to Horford (without Big Al's sweet offensive skills, obviously).
Anyway, I didn't want to discuss Looney in this space — just noting that in this comparison the Warriors' non-Draymond center minutes need to be thought of as Jones + Looney + a bit of Bell (+ eventually Cousins), not just Jones. The main point is that Horford plays a far bigger percentage of his minutes as the team's sole big man than Draymond does. I think Ben Hogan's point is that the Celtics would do well to dial down Horford's C minutes, not necessarily to Draymond level (since Horford is a bit better suited physically to the task), but some.
Of course, with Theis hurt and Sleepy developing in Maine, that may be easier said than done. 10-15 minutes per game of one or the other would probably solve the problem, such as it is.