It's possible that content-based suppression happens, but it's also possible that the genericized phrase organically generates more engagement by virtue of it being likeable to way more people. If all your followers celebrate the same holiday then it should be a wash but if huge chunks don't then it's purely the numbers doing their thing. Even some who celebrate the mentioned holiday might find the message exclusionary enough to not engage (a woke feedback loop, you could say), further burying it.