Once again, Ed nailed it. I feel about the same way about "flavor of the month" trends. I'm fairly conservative about steel, and as a new maker I try to learn about alloys that have been around awhile and proven to work really well.
On the other hand, I may be a bit of a black sheep in that I love "plain" high-carbon steels, tool steels,
and "stainless" steels. I feel each type has its own attributes and see no reason to restrict myself to one or the other. I used to be a complete snob about high-carbon simple alloys, but research and some personal testing has taught me to open my mind a bit.
I've used several different steels but I'm now focusing on O1, D2/CPM-D2 and CPM154, and phasing out the other stuff I have on hand. I know they can all make excellent blades in their own way and I hope to get a good grip on understanding those three.
If you like 440C, you'll love CPM154. It was designed specifically as an improvement on 440C. It has somewhat better corrosion resistance, edge-retention and toughness. It polishes up really nice. I've ground both and can't really tell the difference that way, both are reasonably easy to grind and drill. Go for it!
Another kind of unpleasant reality is, as you mentioned, 440C (while it's still a good alloy) is often seen as being "outdated" and that may affect sales. Part of this might be because so many mediocre or worse knives have been made of cheaper 440A or 440B, which really don't compare to high-carbon 440C.
P.S. D2 isn't a stainless steel, it's a tool steel. It doesn't have quite enough chromium to be called stainless. (sorry, Ed, I couldn't resist being a smarty-pants

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