Yes. And one of the first things Microsoft did when they bought Bethesda was to remove their games from GeforceNow.

They've made deals with GeforceNow to keep ATVI games on there though.

Why can't Microsoft buy the services they want from Activision without buying Activision itself.

The only reason I can think is to prevent others from using those services which is anti-competitive and harms the general public.

I'm aware it happens all the time elsewhere.

Because they want King for the mobile gaming aspect. They were preparing to launch a mobile game store on iOS once sideloading is allowed (rumored to be soon in Europe if not everywhere)

Then they should commission King to create content for their platform, or make their platform competitive with IOS/Play/Samsung stores to attract publishers.

Platforms buying their content creators to make them exclusives is anti-competitive so I'm glad the CMA has done something, wish they would do it more often.

Why can't Microsoft buy the services they want (King) from Activision without buying Activision itself?

They don’t want services, they want to own the product and grow those product revenues

They might claim that... I suspect what the really want is to make the acquired products/services an exclusive of their own platform.

Yes, which is why I don’t understand how ‘market forces’ ( I’m quoting the cma) will magically improve things for me, the end user/ consumer.

What I want is a simple regulation which says that if I buy a game, I should be able to run it locally, or on a rented box, whether operated by a third party or not.

Yes. If you have Gamepass on the Xbox you can, for many games, choose between installing a game locally or playing it "in the cloud". It's quite frankly a fantastic feature for all those time you want to try out a game, but don't want to clear 100 GB of free space on your Xbox hard drive to actually download the game.

Also fantastic for those of us who only have a work laptop and don't want to buy an expensive console or PC to play the occasional video game.