I think it comes down to style, this guy isn't a looper, he's a counterhitter/blocker. So when the spin changes aren't that extreme he does better.
I was that kind of player for a while and in some ways I still am so I know exactly what you mean.
But I think it is just better to say that you play better vs what you practice against and what you understand. I understand why people complain about pips. At every level, you have to practice against them to avoid losing to them and it can be bothersome if you don't. But since we have lots of pips players in Philly, I actually got decent against them pretty quickly and struggle more with the inverted ball.
Today, I played a guy with long pips and didn't even realize he was using long pips. A teammate of mine was disgusted at how he looked and called him a basement. Another teammate beat him at 1,2, and 4 or something like that (his main practice partner is a long pips expert who has been as high as 2300) and said that he could not believe that his opponent was 1700+.
I actually won the first 2 games against the guy without realizing that he was using long pips. He had shown me the pips but I failed to register them! In any case, our match would not count as our team had already won the match. After I beat him, my two teammates and I had this conversation about pips which guides what I write below.
The idea that players who can't play pips don't understand spin is simply untrue. It's really that players who haven't practiced much vs pips respond to pips as if they are inverted rubbers as spin reading happens at a subconscious level. We make assumptions about our every day environment. After all, I am far better at looping backspin than I am at looping topspin and no-spin because I never looped topspin until I was maybe 1900-2000, while I often looped backspin even when I Was 1400 as I wanted to learn. No one explained to me that you could loop any ball as long as you adjusted your stroke to the contact point so I thought of every loop as a special technique. But even now I intellectually understand spin, I still struggle to read and loop non-backspin balls instinctively as my instinctive loop is vertical. I can do it, but it is a struggle.
And I have seen guys who are 2200 and have taken 2600 players to 5 games lose to 1800 players who used pips. So which is more likely - they cannot understand spin when returning 2700 serves, and therefore lose to 1800 pips players, or they just haven't practiced vs pips and therefore struggle to play competently against them? You mean losing to DeWitt means you don't understand spin? Seriously?
I will close this out with one more story. Back in 2012, I was about breaking 1700 and playing at the NA Teams. Myself and a couple of my junior teammates played a guy rated 1600 or so. And my teammate came back and gave the first game score as 11-2 or something ridiculous. And after, he was like, we should all beat the guy, because he discovered that if he served long no spin into the guy's pips, the guy would just chop the ball off the table. And after we all beat him either 3-1 or 3-0, we all asked the same question - how could that guy be 1600?
I think we all know the answer - he takes advantage of the fact that people don't get much practice vs. pips.