As I have already said, that MS has it more than difficult to demonstrate irrationality to the CAT, is unquestionable.
I already said in another thread that, in my opinion, MS is fighting against the FTC more with a view to future acquisitions than with the hope of acquiring ABK. If MS wins in the USA, the CMA will be alone and that will put it in an awkward situation the next time they meet.
But I repeat, There Is no consensus. It is not irrational either to defend that it is not a market.
Experts, top people in the industry, some regulators...?
Both have the same purpose and business base. Distribute games. They both compete with each other. The success of the consoles affects Stadia (and the like) and vice versa. The games are the same. And they are offered within the consoles themselves as a complement to the physical game.
I believe (and clearly many people in the industry) that there are enough connections and dependencies between the two that makes considering that they are different markets certainly is not something objective.
Just like the FTC and CMA do, support the argument that benefits them. That doesn't make some more right than others. In a space of lack of consensus in the industry, everyone chooses to defend the description that is best for their interests.
If the CMA were arguing that cloud gaming is not a market...MS would have just as hard to prove irrationality.