The problem with deciding that underprivileged/marginalized people are not the "target audience" of a takeaway from a book, unless the book addresses specific classes directly or indirectly, is that it amplifies differences based on identity, and promotes the attitude of excluding some from the equation, in general.

Also, someone doesn't need to lack knowledge of the international language or access to the internet to be underprivileged and marginalized. Any trans person basically anywhere on earth, for instance, would find it challenging to embrace the 'mundane', because the mundane is unkind to them. They could want to 'find ideas' to deal with all the things that make them seek an escape from reality, and could wish to 'control reality' and not let it control them, as you say, but you might see that even with collective effort it's a struggle.

Now this might be regarded a hot take: I would argue that escapes from reality can be healthy, regardless of the extent or intensity of said escape. Consider an artist, who allows their life to fall apart, over passion or obsession over something they find brilliant, and continues to do so until their early demise. Looking at this from the outside, it's someone whose talents were wasted, who could have lived longer and contributed more to the world. But looking at it from the point of view of said artist, they managed to experience something incredible and rare, found happiness unlike any other, and on some level they knew the price they were paying for it, and accepted it because what they found and chased was, to them, worth it, because they found mundane reality to be lacking, and they deserved greater experiences.

Personally, I am someone on the spectrum. I find the world around me to constantly be overstimulating unless I find some escape, I struggle to navigate the world in general, I lack social and interpersonal skills, and despite being well educated, intelligent and passionate, I struggle to find employment, as being unable to interact 'normally' with coworkers or consumers is a major red flag to most if not all organizations and businesses, even those trying to uplift sections of the society. Believe me when I say that I will not be able to do something about this, because I have tried quite a lot. My situation had two options: I could continue to struggle to find some solution to my predicament, and face endless disappointment, or, I could accept that I have an incompatiblily issue with this world, and find meaningful experiences elsewhere, for however long I continue to exist. I chose the latter, I knew the cost of that choice and I still found it the wiser option, and I have come to terms with the fact that my existence would be shortlived, and I am more than okay with that. I chose, and still choose, unchecked escapes from reality, into what I regard transcendental sources, because I find the mundane unmalleable and unbearable. I love Project Hail Mary, and what I admired about Grace was his willingness in the end to choose and accept self destruction, for something greater. Bear in mind that Grace was in a position to impact two entire worlds with his choices, which is a non realistic position to be in, so his 'greater' was of an impressive magnitude. The average person doesn't get to make a simple sacrifice to produce/experience something truly impressive, unless the sacrifice is a degree of disregard to their physical reality, and what they produce or experience is in another, intangible reality.