K/O are known to be more consistent on their jumps. But the Knierims have improved some aspects of their skating during their short time with Aliona, and with the work of their choreographer, Benoit Richaud. I really don't see how you think K/O's lifts are of a better quality than the Knierims. I think it's probably a wash in that category with the Knierims possibly having the edge more-so than K/O. Plus the Knierims definitely have a boffo 3-twist, and more explosive power on their throws. The Knierims may also have a tad more speed than K/O, or it's a wash there too. Both teams have different styles and personalities. But there's really not a huge amount separating them, aside from K/O's reputation for consistency vs the Knierims' explosive power, and hugely better 3-twist (in addition to probably a bit more appearances in front of international judges), and having previously held the highest placement at Worlds among current U.S. pairs teams.
I realize that Tarah and Danny are slowly trying to improve their 3-twist under Sappenfield, but they aren't there yet. I'm not really rooting for one team over the other. Neither have been my top favorites over the years, but I do like both teams, and I will be happy for either. The main thing is being sure the strongest team is sent in order to get back two spots. And so that means being strong mentally too!
What is hampering the Knierims has been their confidence ever since coming back from Alexa's illness and surgery. I also think their confidence was likely impacted by negative comparisons and expectations made by fans in the lead-up to the Olympics. Alexa seemed a total wreck at Nationals under the pressure of wanting to win the spot on the team outright rather than being seen as losing Nationals and then being rewarded the spot. That scenario seemed to have worked on Alexa's pysche.
Putting that aside, what happened at 2018 Worlds was unfortunate. It's too bad that K/O weren't stronger physically in coming off their 4CCs win. Had K/O been healthy and able to attend Worlds along with the Knierims maybe they would have been able to make the cut and contribute toward the U.S. not losing a second pairs spot. Stellato/ Bartholomay are not to blame either, as they performed decently well in the sp in Milan, but were given short shrift and did not make the cut due to little fault of their own IMO. The biggest blame goes to the ISU for setting up the competition in such a limited way for pairs teams at Worlds when it has been such a deep field over the past several years.