Of course it is his opinion
The problem is not his opinion, the problem is that quote (I don't know about the book) provides zero arguments or evidence for it. It's written for people who already agree with it, and even those won't learn anything from it, other than just maybe getting a warm fuzzy feeling.
What makes the passage effective, to me, is not that it should be read as a literal claim about every priest. If you read it only as a literal claim, you are almost guaranteed to miss what the passage is doing. Rather, it works as an exaggerated and provocative compression of the gap between Christian moral language, institutional religion, and God.
Indeed provocative and provocative only, as again there are no arguments provided. So it indeed intends to provoke emotions.
It's not even very good at that, much has been written about the topic during the last five centuries (and more), both with and without arguments. Screeds about Christianity being a Big Lie are hardly novel.
I think it is also important to realize that this comes out of Shamanic Nietzsche, where Land is not doing a traditional reading but dissecting Nietzsche’s thinking in a very different way. In that sense, I think he is actually doing a good job, even if he does it in his own style. It is radical, and precisely through that radicalization he forces a different mode of thinking. What Nietzsche would call ressentiment is here turned back into a direct attack on priestly morality.
I suppose and hope that the rest of his work is better than that quote (which may itself be better in context). However, I'm replying to your post, that contains that quote and doesn't provide any context in it other than a full book.
The reason I chose that quote is also tied to how Christianity is currently being used, and the tensions and conflicts around it that are becoming increasingly visible. Even this week, in the friction between some world leaders and the Pope, or in wars framed in Christian terms by figures who themselves carry the symbols of crusades on their skin, you see how charged this terrain still is. That is why Land, for me, feels relevant it’s not just abstract radical philosophy, it is still actively unfolding, as is the obscenity of Christianity.
I don't disagree about the use of Christianity, however I would argue that in my opinion that "currently" has been current for over 16 centuries. Now, I don't think Christianity is inherently "obscene", and as you may understand I won't just be convinced by a vehement statement that it is so.
All this is besides my point here, as I'm not arguing about the idea presented, but the complete lack of anything resembling arguments, evidence, or nuance.
That is mainly how I read Land, not as a balanced philosophical theory, but as exaggerations that provoke thought.
I understand that, I do like to read provocative thinkers too. But again, does the statement "Christianity is maximally false" by itself, with no rationale given, provoke thought in anyone in 2026? Believers will obviously just reject it (and rightly so as long as zero arguments are provided), and non-believers will either shrug ("yeah I agree there are many lies there, however that seems somewhat over the top") or cheer if they already agree. No one can learn anything from the quote provided, beyond facts about Nick Land himself.
I think there's a more important point here, and is that the quote, as provided is out of place. It explicitly attacks a whole group of population without providing any arguments. It's just "boo outgroup!", "a religion I disagree with is a Big Lie!", "their priests are liars!". Whether one agrees with the quote or not makes absolutely no difference, it's an expression of an attitude that's out of place both in this subforum and in the Nexus in general.
It's perfectly possible to criticize Christianity providing reasoning and arguments (as you do in your second post), but the quote fails to do so, and the post itself fails to provide any additional context that could make it into something different than the equivalent of spitting in the ground. If I fully agreed with the sentiment expressed there I'd still think the quote is out of place here, at least as provided.
I'm going to illustrate this more clearly with a specific example. I don't agree with the following quote, nor think it would be fitting to post it without context in a post, and I think you'll agree with me on this latter part. It matters little if one is to agree with it or not to establish that it would be out of place in the Nexus:
Martin Luther said:
Therefore be on your guard against the Jews and know that where they have their schools there is nothing but the Devil’s nest in which self-praise, vanity, lies, blasphemy, disgracing God and man, are practiced in the bitterest and most poisonous way as the Devils do themselves. Wherever you see or hear a Jew teaching, do not think otherwise than that you are hearing a poisonous Basilisk who with his face poisons and kills people. Through God’s wrath they have been delivered to believe that all of their boasting, vanity, lying to God, cursing all men, are right and a great service to God, something well becoming to such noble blood of the fathers and circumcised saints (no matter how mean they otherwise might know themselves to be in gross vices) which service they think they have rendered hereby. Look out for them!
"Boo outgroup, religion X is a lie because I say so!!!!!!111"
I would expect anyone that posts this without further elaboration to at least get a warning, probably be banned.
So, feel free to argue against Christianity, but please provide arguments, as you have done in your follow-up post. Avoiding emotionally charged language when dealing with these topics is also a good idea.