I get the feeling you're being rhetorical, but if I remove the tone in my head then: yes, clearly.
> out of control with everyone poaching each other's customers blatantly
Corporations shouldn't own customers... Like, the way you poach one is by offering a better deal (more features, better price, better service, etc). I think the way an economist would see the situation you are describing there is a "functioning market" -- the way that an economy improves customers life.
If AMD releases a new processor and "steals" a ton of Intel customers that's a good thing. The customers get better processors which they use in their own economic contributions. If Intel steals them back by releasing an even better processor, that's also fantastic. If that process repeats it's not "out of control" -- it's the world becoming better.
This dynamic (competition) is the reason why capitalistic societies have done so well in the last two centuries. It's the reason why the quality of the goods you use continues to increase while the price drops.
When corporations make an agreement to stop competing on any dimension, that dimension suffers. Maybe you're saying you don't care about this particular dimension. If that was true in general (ie no consumers care about the dimension), then the agreement wouldn't be necessary since competing on that basis would have no effect.