Maybe it's different in the US and other cultures, but as an atheist I've never seen the phrase as a very religious thing. I say "merry Christmas" and "happy holidays" indistinctly and I've never seen anyone offended by the use of either, independtly of their faith (or lack thereof).
I say "merry Christmas" on the actual Christmas day though.
If on Android, revanced works wonderfully. On iOS you can just use adguard and safari instead of the app. At least that's what I use and I only get ads when I use the default yt app in my oldish Hisense TV instead of casting or just my PC.
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