My .02 as somebody that really liked K2 for a long time...
I owned a pair of Recons, Kung Fujas, and Obsethed. The Obsethed is the only one still around, and it is only used for rock ski duty. It isn't a ski I terribly like any more, instead it is a ski I use to avoid traumatizing the skis I actually like.
I think where K2 fell short is being really late to the 5 point ski party.
Rossignol came out with the S7 a LONG time ago at this point- 2007 if I am googling correctly? K2, while being right on top of the rocker craze (and probably being too eager on that front, adding marketing rockers to skis that really didn't get a benefit from it), they really only started selling 5 point designs last year with stuff like the Shreditor, Annex, etc. Sure, they had the Pontoon nice and early, but that was a very niche ski designed for maybe 1% of resort days where the S7 became a snowy ski area everyday darling.
When rocker first became a "thing," it sounded wonderful- better float and better smear in deep snow, sounds great! But when paired with a traditional sidecut as many companies rolled out, the experience was really underwhelming. You couldn't really smear the ski because the tips would catch and the ski would not be predictable. Meanwhile, on hard snow the tip is off the snow, and when you haul the ski over, the tip comes back into contact mid-turn and that can make the ski behave unpredictably too.
After skiing two fatter skis with traditional sidecuts (the K2 Kung Fujas and Obsethed) I felt rocker was overblown and mattered a lot less than ski design. Neither of these skis would smear worth a crap, and my experience skiing trees with them was that I was very timid as I had no brakes if I skied into something I didn't like- I had to wait out the turns to make the ski behave predictably.
Getting on an S7, I instantly saw the design problem in full sidecut and rocker. The S7 smeared and played like I expected all those rockered powder skis to do for years. It was exactly as fun as I had been lead to expect, and before getting on a powder day, I though an S7 was a gimmicky "Six of all trades" ski that was trying to do too much. In fact, once you get over the short running lengths, 5 points can be more capable skis on hard snow than a traditional sidecut wide ski too, because you have a ski tip (in the 5 point case, the widest part of the skis) that is always in contact with the snow.
So, I think I lot of people like me jumped off K2 when they discovered that 5 points where the future in powder ski design, and K2 offered NOTHING. K2 had given up racings skis years ago, they jumped headlong into rocker, but then they missed out huge on the next (more important) leap into 5 point skis. They were left with a company that didn't sell race skis, didn't sell modern design powder skis, and had a large line of generally forgettable skis in the middle.
FWIW, I wasn't terribly impressed with the Rictor when it first came out. It seemed like a rebadged Recon with a tiny amount of marketing rocker that didn't really do anything for the ski.