The authors are US-based, but the journal (Mol. Phyl. Evol., published by Elsevier) is a Dutch multinational with a global readership; to make the assumption that 'sparrow' can only refer to Passerellidae is something where I definitely do see an issue.
Couple of pretty shocking errors in this paper, hope they can correct them before going to print:
Passerellidae never has included any of those genera; they were, are, and always have been, in Emberizidae. A better wording would be:
And the title
is also inaccurate and very misleading...