Incel communities are different from Christians struggling w/ desiring marriage. They tend to want women (& yes, I say women, plural) for the wrong reasons. They don't want marriage. Not a healthy one, anyways. Or they have a skewed perception of what a healthy marriage is. They want someone on their arm. They want it because someone told them they should want it. They want it because they saw someone happy in a relationship once & decided they wanted it too. They want it for reasons that can fade over time. They're looking for something in the short-term & not recognizing responsibilities & what may be asked of them in the long-term.
My frustrations have taken me to communities that have had it hard with the opposite sex like me, communities that have no problem with the incel identity, l but as a Christian I can't view it in the way they do. Their mentality is visible in ALL that they do & say & extends beyond whatever it is they think is the source of their frustration. It's more than just 'God is unfair'; it's a 'the Christian god doesn't exist period'.
Christians definitely shouldn't use their relationship status as their identity, nor let it drive their emotions or actions or take away from their trust & joy in Jesus, absolutely, but I can't say it's wrong to be upset about, & a post expressing some discontentment isn't necessarily an indicator of overall mentality (or faith) either.