I can't agree. It's true that 1P isn't as shot-intensive as other games, but the shots you have to take in 1P are way more difficult on average than shots in any other game, and almost all of them must be two-way shots.
More importantly, I don't think pocketing is "the one thing pool is all about". Of course pocketing is essential, but IMO cue ball control is the "art" of pool - pocketing is the "strings" on which the "music" of CB control is played. And CB control is more important and difficult in 1P than in any other game, IMO. On top of that, you have to control the speed of both the CB and OB on almost every shot, which is unique to 1P (along with the frequent circus shots that come up).
I'm not saying 1P is the "best" or even most demanding game - I don't think the apples and oranges of the different games can be clearly compared like that. They each have their strong points and none, in my opinion, dominate overall.
pj
chgo