I think the K would likely be both simpler and harder than your first example by reading very straightforwardly in a single direction but with operators reading like line noise. In your case, my Numpy is rusty, but I think this is the Ruby equivalent of what you were doing?

    textb = 'What hath the Flying Spaghetti Monster wrought?'

    p textb.bytes.product((0...8).to_a).map{_1>>_2}.map{_1 & 1}

Or with some abominable monkey patching:

    class Array
      def outer(r) = product(r.to_a)
      def right_shift = map{_1>>_2}
    end

    p textb.bytes.outer(0...8).right_shift.map{_1 & 1}

I think this latter is likely to be a closer match to what you'd expect in an array language in terms of being able to read in a single direction and having a richer set of operations. We could take it one step further and break the built in Array#&:

    class Array
      def &(r) = map{_1 & r}
    end

    p textb.bytes.outer(0...8).right_shift & 1

Which is to say that I don't think the operator-style line-noise nature of K is what gives it its power. Rather that it has a standard library that is fashioned around this specific set of array operations. With Ruby at least, I think you can bend it towards the same Array nature-ish. E.g. a step up from the above that at least contains the operator overloading and instead coerces into a custom class:

    textb = 'What hath the Flying Spaghetti Monster wrought?'
    
    class Object
      def k = KArray[*self.to_a]
    end
    
    class String
      def k = bytes.k
    end

    class KArray < Array
      def outer(r) = product(r.to_a).k
      def right_shift = map{_1>>_2}.k
      def &(r) = map{_1 & r}.k
    end

    p textb.k.outer(0...8).right_shift & 1

With some care, I think you could probably replicate a fair amount of K's "verbs" and "adverbs" (I so hate their naming) in a way that'd still be very concise but not line-noise concise.