If they get declared a gatekeeper, yes. Until then it doesn't apply.

I'm not sure they meet the requirements of being a gatekeeper. One of the requirements for example is 45 million monthly active users in the EU. According to Microsoft, Xbox is only at 4 million:

https://support.microsoft.com/en-us/account-billing/informat...

Playstation and Nintendo might be more popular, but 10x more popular? Even the Switch has only sold 6x the Xbox Series consoles.