וְשֵׁם אֱלֹהִים אֲחֵרִים לֹא תַזְכִּירוּ לֹא יִשָּׁמַע עַל פִּיךָ” (שמות כ”ג, יג
I dont know all the halochos but isn’t this posuk the reason we say xmas and not use the name jc ?
And if yidden never said or wrote his name out but called him yoshke then there must have been good reason for it.
And for the person who mentioned not using Hitler’s name etc I know that there were many gedolim at that time who didn’t mention his name .One was R Aron of Belz and I think one of the readons were not to give “koiach”to the sitra acrah or something like that