I’d like to point out that for the January 6, 1979 chart, “Christmas Portrait” is the only Christmas album on the Top 200 chart. All the other 199 albums appear to be non-seasonal and greatest hits packages.I largely agree with Rumbahbah regarding LP Christmas Portrait.
But, I do note that Billboard ran (at least) two full-page Advertisements for that album,
issues November 11, 1978 and December 23, 1978. Both ads touted the upcoming TV Special,
a special entitled Christmas Portrait.
Now, perusal of Billboard Charts for the beginning of Jan 1979, shows the LP at
#145, after FIVE Weeks ! That is indeed a dismal showing.