"But since Jesus never taught His apostles to keep Christmas, ...., shouldn't that make us question whether Christmas is something Jesus really wants or appreciates?"
The logic of this line of argumentation is so laughable, that I can't believe anyone would take it seriously. To illustrate, let's substitute something else that Jesus never commanded His apostles to do:
"But since Jesus never wrote anything Himself and never told His apostles to write the New Testament...shouldn't that make us question whether the New Testament is something Jesus really wants or appreciates?"
Gee, its really true folks - Jesus never wrote anything in His whole ministry - let's all burn our bibles now!!!
And as for all the posturing about observing the feasts that our Lord appointed, I bet the author completely rejects the books that describe the institution of Hannukah, never mind celebrating the feast as Jesus did.
It's perfectly logical considering that Christ created specific days that he commanded that his followers should observe. As followers of Christ...."Christians"...we should live by the example he set in the records of his life and observe the festivals he created and observed.