No, no religion should have a federal holiday.
I too want them to stop preventing the free exercise thereof. Laws that try to make Hobby Lobby fund what they see as abortion or forcing Catholic adoption agencies to allow gay couples are also wrong. I just also see this as wrong too. Not a big wrong, or even one that's worth any political effort, but still a small wrong.
I get the founders used some of it, but they were not perfect, and also violated a bunch of the rest of the constitution also, including the Sedition Act violating freedom of the press, etc.
And if I recall, the reason that it hasn't been overturned is solely because it is viewed as 'ceremonial deism', i.e. it has lost all religious significance and is just a patriotic statement. Personally, I don't buy that, but that's the excuse it's let in under.