I will try to help:

The first feeling that washes over you is a kind of despair that this question was asked at all, as even a cursory view of the information available in the OP, let alone a Google search, would immediately show the project is not related to ReactJS. You find it difficult to imagine the kind of mind that chooses to seek trivial answers from others rather than attempt to answer them on its own. This mind thinks nothing of wasting the time of others to satisfy its own meager curiosities. Surely, in this case, the time taken to ask the question takes almost as long as the research required to answer it.

However, you can't help but notice a deeper level of sadness swelling from below...

It's not merely that the question was trivial. For example, the question "What is this project for?" doesn't seem nearly as sad. Moreover, we notice that if ReactJS was an obscure or unpopular project then this user's question seems rather innocuous.

We see that your deeper sadness stems from the realization that this user is consumed and infatuated with the present trend in software development, whatever that may be. If he knew, he would not care that ReactOS predates ReactJS by nearly two decades. To this user, what exists now is better than what has ever existed before. After all, he imagines, every good idea and enlightened thinking in the history of computing has been brought to the present; these qualities are easily recognized by everyone and they naturally persist and become popular. Therefore, the popular projects are the best humanity has to offer both technically and philosophically. Likewise, obscure, small, or old projects have the opposite quality.

Learning of ReactOS for the first time, he is skeptical of how much of a "good idea" it could really be (surely he would have heard of it by now if it was worth knowing about). So, he attempts to establish the project's merit using the only method available to him: an appeal to popularity. Does this project relate to the current pinnacle of computing achievement, ReactJS? Being a React aficionado, he doesn't suspect it is related but decides to ask anyway just in case he missed something. He wants to know the answer, but ReactOS appears sufficiently unpopular (ie. irrelevant) as to not be worth any appreciable time or effort to discover it for himself. Besides, it is far more agreeable to his psyche that the crowd provide the answer.

There is a subtlety to the user's phrasing that enhances your sadness further. He does not wonder "is it related?" but rather "does this have anything to do with?". One gets the feeling that if only there were just the tiniest bit of relation to ReactJS then this user would be satisfied that ReactOS is indeed a worthy project.

There is a sense that this brand of thinking is 'shallow' or 'myopic'. That it is a brand of thinking that is destined to bring the industry to a state of perpetual mediocrity caused by the incessant following of trends instead of truth. That it is a brand of thinking that causes those under its influence to ignore the search for truth altogether as they are assured that truth is always provided for them, right here, in the present. And when real truth does arrive in those rare moments, it is a brand of thinking that renders it unrecognizable. This is troubling but it's not the sole cause of your depression now.

You are saddened because you know he is one of many.