Microsoft would have to conspire and use its monopoly powers to undermine and place barriers to entry of SkyDrive's competitors, for something such as the above to happen.

Bundling or providing for download a cloud storage application or service is not illegal. Having a monopoly is not illegal. Providing useful applications and features with Windows is not illegal.

Don't want SkyDrive? Don't use it. Do as you did before, download your choice of a cloud storage application and use that instead.