#that he was able to convert some anti-Semitic tropes to be positives in his value system doesn't change that

[anarchotolkienist]

Specifically it goes back to Nietzsches Genealogy of Morals and The Antichrist, where he identifies Christianity as fundamentally a Jewish religion who grew out of the priestly caste rule (rule by the weak) and the resentment felt by the Jews at their domination by other peoples, especially the exile in Babylon and slavery in Egypt. Thus Judaism (and through Judaism, Christianity) exalts the weak and debases the strong, it is a true slave morality (quite literally, the morality of slaves, rather than the morality of slave owners, as he would prefer), and it was in its changed form as Christianity that Judaism would dominate and defeat the Aryan, dharmic morality (and, his pagan followers would add, religion) of the European aristocracy that he so adored.

For every claim about Pagan survivals in European / North American folk traditions and holidays, it's important to remember that there are at least three layers of cruft on top:

Sixteenth- and seventeenth-century Protestants trying to discredit Catholicism by claiming that it was secretly Pagan

Nineteenth-century Romanticists and Nationalists trying to construct an "authentic" volkisch identity by connecting everything to a remote pre-Christian (pre-Jewish) antiquity, and

Contemporary Neopagans and New Agers who want to maintain these traditions.