I think it would be better if he said something more general, like the holidays are a busy time for everybody. But I totally agree that something should be said to indicate interest, to not leave anyone hanging.
As for even looking at a phone during a date, that's a huge red flag for me, but I'm biased because I despise our cell phone society. Seems to me if someone's family or friends are requiring a check-in (something I'm not particularly fond of, either), the person should go to the bathroom to do it. Unless, of course, they want to put their date on notice that the cell phone is of at least equal importance as the person on the other side of the table.