Christianity can't really be a cult because it isn't centralized at all. There are definitely christian denominations with some cult like qualities, like the mormons and jehovah's witnesses, but christianity as a whole is definitely not a cult.
To be clear I'm definitely not saying christianity is good, it has as many problems as any other religion, it just isn't really a cult, if we apply the word cult so broadly it loses it's usefulness. If we say christianity as a whole is a cult, then we need a new word to refer to the actual individual groups within christianity that we would usually call cults. It doesn't really make sense to say that mormons and jehovah's witnesses are a single cult, so what would we call them? There's an important distinction to be made between a single group with strict control over its members and a general set of beliefs.
There is no requirement that a cult be centralized. Christianity and other religions are essentially fandoms(or tribes) organized (somewhat loosely) around shared principles. The major difference between a cult and a fandom is if it is deemed socially helpful or harmful by society (or the ruling class) at large.
I usually use the BITE model when thinking about cults, and it's kind of difficult for something without any central government to be very culty with that definition. It definitely could be with a different definition though
Looking it up, BITE stands for Behavior, Information, Thought, and Emotional control.
I still think Christianity and religion can be a cult because it is a shared belief in a higher power. And if you mention anything that they perceive as contradicting that belief they will mentally discredit you.
Using the bite model, it is still a cult. The only difference is the degree. The bible clearly labels certain behaviors as bad and others as good. Christians claim the bible to be the one the one true source of authority for the christian faith (for protestants). The implication is that any other source of information that challenges it is wrong. The bible clearly labels certain thoughts as sins and active discourages those thoughts. By labeling even thoughts as sinful and therefore bad it encourages feelings of guilt, and by calling all humans sinful it encourages fear of others. Hence controlling our emotions.
Of course, different denominations will vary in how they think Christianity should be put into practice, but I would wager it is trivally easy to find elements of behavior, information, thought, and emotional control no matter the denomination.
Cult Is just the English version of the French word culte which means the public practice of worship, devotion, adoration, veneration or exaltation. A lieu de culte is any place of worship like a church, a mosque, a synagogue, or a Babylonian temple. Le culte protestant is Protestantism, le culte du soleil means "sun worshipers," le culte de la performance means the veneration of productivity and competition, and a culte de la personnalité is the adoration of and obedience to a person - whether spiritual, political or entertainer.
This use of the word cult still makes the most sense in English, because we could say all of those French phrases in English and anyone would understand what they meant.
Therefore, by extension, all religions or sects that include devotion to a deity, person or idea are cults including Christianity as a whole and each of its denominations.
Regardless of the etymology, that's clearly not how it's used in modern English. The person in the original post definitely didn't mean "It's giving theistic religion, friends"