I dare to be a little excited about this. Formally including opensource in the criteria is an amazing step and could unlock major funding.
If this doesn't just apply to services governments buy to operate but services they host to communicate, twitter, Facebook, LinkedIn, Tiktok, instagram, Youtube, and others will not make the cut. They are neither opensource nor are they European in any way, shape or form. Having all government institutions in the EU leave those platforms for the fediverse and others... But that's just dreaming at this point.