I believe this is addressed in the rest of the sentence:
Any content type is accepted, but we are primarily looking for Games. If we receive many submissions for other content types, like assets, tabletop, etc., then we may consider creating additional bundles. We don’t intend to mix content types.
Essentially we don’t know what to expect in terms of submissions, so although our primary goal is to create a games bundle, we may end up creating an asset bundle if we get enough interesting submissions.
There have been quite a few submissions so far so we’re probably going to have quite a bit of work to sort through things. We still are not sure what the final composition of bundle or bundles will look like.
Thanks