Elmax is a difficult steel to heat treat, ZT / Kai just didn't know what they were doing with the stuff, or they were too stubborn to get an in house expert on the scene to deal with it, or send it out for professional heat treatment.
That's ZT's reputation in my book not the Elmax steel, but I do see what you mean, sometimes things can stick with you based on past experiences and that's human nature, I just want to assure you Elmax is a good steel as long as you heat treat it as Elmax, because it isn't 20CV, and it isn't D2, it's Elmax and needs to be treated as Elmax.
The same goes for M2 I personally love M2 but I understand knife makers don't want to deal with the M2 heat treating mess, because it requires its own specific heat treatment method, if you heat treat M2 like it's 1095 you won't end up with M2 at it's full potential. I have some M2 professionally heat treated by Eclipse tool company to 65 HRC, and this stuff out performs Spydercos K390 by 50% in all my edge stability and retention testing. It is beastly stuff and not to be triffled with.
I got some good Elmax from Fox knives in Maniago Italy, and the reason why it is so good is because Fox send their Elmax out for professional heat treatment with a steel factory in Italy, a factory that specialize in heat treating difficult steels, they don't do it in house.
Trust me Elmax is perfectly good when done right, just as good as M390, bad Elmax is just that bad Elmax, good Elmax is great.