Reminds me a lot of "the dark night of the soul" as described in "Mastering the Core Teachings of the Buddha" by Daniel Ingram (the book is online at
https://www.mctb.org/mctb2/).
Scott Alexander did a great book review if you want the summary: https://slatestarcodex.com/2017/09/18/book-review-mastering-...
This finishes with a Scott-at-his-best quote that is pertinent to the OP:
> Why would you want to do any of this?
> The Buddha is supposed to have said: “I gained nothing whatsoever from Supreme Enlightenment, and for that reason it is called Supreme Enlightenment”. And sure, that’s the enigmatic Zen-sounding sort of statement we expect from our spiritual leaders. But if Buddhist practice is really difficult, and makes you perceive every single sensation as profoundly unsatisfactory in some hard-to-define way, and can plunge you into a neverending depression which you might get out of if you meditate hard enough, and then gives you a sort of permanent annoying low-grade bipolar disorder even if you succeed, then we’re going to need something better than pithy quotes...
> Once he’s stripped everything else away, he says the only thing one can say about enlightenment is that it grants a powerful true experience of the non-dual nature of the world.
> But still, why would we want to get that? I am super in favor of knowledge-for-knowledge’s-sake, but I’ve also read enough Lovecraft to have strong opinions about poking around Ultimate Reality in ways that tend to destroy your mental health.
Worth noting that as far as I can tell most of the meditation community doesn't get behind Ingram's account of the "dark night", and teachers talk more about having blissful/tranquil mental states available on tap. Ingram might retort that most teachers are full of shit and haven't attained enlightenment, they probably just got first Jhana.
Most people round here would probably read the "fire kasina" and magick stuff that he's talking about after "14 hours per day for 10-20 days in good practice conditions with full, unbridled, undistracted effort." and think -- yep, that sounds like a psychologically risky state.
My general take is basically the same as with using psychedelics for treating trauma and depression; any medicine which is powerful enough to modify your mind and cure major structural issues is also powerful enough to break your mind, if you're unlucky/unskilled/unguided in the application.
The (completely incorrect) Western image of deep meditation as "deep relaxation" is a big problem here, and that's compounded by it being quite awkward to actually claim you're enlightened, which makes it hard to credential-check your teachers; most people straight up call BS on such claims. From the little meditation I've done, I think it's more likely than not that "cessation" / "enlightenment" is a real mental phenomenon, but I'm not sure that it's actually worth dedicating a decade or two of your life to attain.
Having said all that, light meditation / mindfulness practice is well-documented as being beneficial, so if it's helping you don't stop; just don't feel you need to constantly increase your sit durations and go deeper, if you're not doing so with a specific goal in mind and ideally a community to support you.