Ivan,
Ref. the platform choice, only one of those is actually real, the others are powerpoint presentations, models and empty promises from salesmen who will say anything to secure the deal.
That's a bit of an overstatement. Airbus for one has delivered ASW aircraft to Brazil, Spain and Chile - in some cases using the Merlin HM2 acoustics or a version thereof.
Also all those platforms have a huge flaw when it comes to ASW, current generation subs wouldn't struggle to hide from them, future ones could potentially destroy them.
I haven't seen any sub-based air defense systems deployed, although they've been played with since the 1970s. It's still poor odds, particularly against a platform with DIRCM (which is pretty standard on large military aircraft). If you don't succeed with the first shot you are toast.
That said, I have occasionally heard this as a reason for doing high-altitude ASW, but it's not the one I hear most often.