So in similar fashion to what I had commented on related to Islam, this reads somewhat like you might be trying to present the broad issue under discussion as more complicated and more ambiguous than it genuinely is. I don't think swapping "Christian" for "Muslim" makes the exact same questions any more complicated, but I do think doing so in order to sidestep what I had said and instead pose 'new' questions does give an impression that your goals here may not actually be discussing the specific things you bring up.

I also notice that you've gone ahead and filled in answers for me, and even responded to those answers - which does reinforce the impression that there's motive in your rhetoricals, and does suggest some specific biases via what you assumed the answers would be.

Should “Jesus is gay” or “The Old Testament is the most horrific book ever” be illegal? Should we create a new word “christianophobia” for that?

So this gets effectively the exact same answer I already gave above, while discussing your example statements related to Islam. Neither "yes" or "no" in absolute sense - but depending on context and on patterns of behavior. I'm not sure why you expected anything different.

Pretty sure no one bats an eye when those things are said, as it should be of course.

I take it you're unfamiliar with the American Bible Belt, who - among many heroic feats of absurd oversensitivity - at one point thought a red paper cup was "Satanic" and have felt profoundly oppressed and like their beliefs were under direct assult due to teenagers working in grocery stores not wishing them "merry christmas". This is the same group of people who very genuinely believe that "gay people existing" is exactly identical to "genocide against Christians" and have seen cross-like shapes - "an X" for instance - interspersed with with effectively anything shaped like stars, sixes, the colour red, rainbows ... fuck it, anything that isn't "Jesus" to be subtle or overt disrespect of their faith and them personally.

So no. People of Christian persuasions will absolutely "bat eyes" at some of the most ridiculous shit imaginable, and those Christians are representative of all of Christianity as a whole in scale exactly parallel to the Muslims you were talking about prior representing all of Islam.

However, you wouldn’t have written your long prose if we replaced “islamophobia” with “christianophobia” and that’s what I find sad.

I think you've been reading evidence to the contrary in order to get to this sentence. That said, I'll grant you - “christianophobia” is not nearly as loaded a term and bigotry against Christians is not a genuine societal problem that Christians face in the English-speaking world in the same way that Islamophobia is, so I would have been more likely to assume it was a bad-faith word-replacement than a genuine and sincere statement about Christians and their sensitivities.

I am a firm believer that all Abrahamic religions are harmful and among the most shameful ideologies humanity has come up with, and I believe in the sacred right to disrespect and ridicule those beliefs.

That's nice. It doesn't read that way. The biases you showed here, the answers you filled in for me, do seem to treat Christians like they're obviously the well-adjusted normal people, even as if they're not "sensitive" and totally don't ever get offended by utterly trivial nonsense - while your prior comment sure did make some pretty sweeping generalizations about what Muslems in general think or are saying as far as their responses to similarly trivial nonsense. I think the decision to represent Christians according to moderate and well-adjusted members of the faith, and Muslims according to the extremists is a bit of an interesting pattern across these two remarks, and adding the context that all of those remarks are made in defense of an apparent desire to say some specific shit about Islam and represent it as completely normal and good-faith ...

Don't get me wrong. You can say what you want. Other people can say what they think about that. Some spaces may decide they don't want you in them. I don't think you're holding the moral highground you'd posture towards if you say some shit that sounds "islamophobic" and then act like they're overreacting and oversensitive for calling it that - when it seems pretty clear you're as sensitive, if not more so, to your own statements being labelled according to the broad category of speech that it most clearly resembles.

And in general - Christians ain't immune either; but "I'll be shitty to everyone" doesn't mean that you're not being shitty at all - or even that you're not necessarily targeting one group and just taking potshots towards the others to obscure which was the intended target.