Complete and utter foolishness. The people in this article are indicative of the liberal mindset at its worst--"inclusion" has been corrupted to mean "pushing Christianity out of a majority-Christian society."
As an atheist, I celebrated Christmas. The religious part I just viewed as cultural. I could sing “Silent Night” without being offended. It was a cool song.
As a Christian, I celebrate the Winter Solstice by toasting the coming of longer days and feeding the birds. I see no religious point in it but I don’t get invitations for Solstice parties anyway. Buncha scrooges.