Why should it? Edge retention in Larrin's CATRA tests was about the same, with the bonus of higher corrosion resistance in ZDP189.
Toughness is probably higher in thin edges in K390, but I've used ZDP189 knives in 'hard real world use' for a while now and have no complaints.
From memory, I think it was Cliff Stamp who made the point that the blade steels used in the Seki line like Super Blue, VG10 and ZDP189 pretty much covered the market niches of a low carbide, high attainable sharpness non stainless steel; a balanced everyday stainless, and a high wear resistance steel. I doubt that even most knife steel nerds would be able to consistently identify the difference between each of those steels and their common competitors in those three categories, if they were given identically ground knives in blind tests.
He also noted that when microbevelling edges, simply applying an apex that was more acute by 2 1/2 degrees on VG10 would result in similar edge retention to CPM S30V.
All three of those steels, including V-Toku 2 and the Shirogami/White Paper steels were specifically designed to be high quality, enduring bladesteels.
Of course, like everyone else, I'm very eager to see how SPY27 performs relative to them.