The starting assumption of a secular meditator (like me) usually is that we want to develop some abilities. You are you, just better.
If you meditate a lot, or very long time, there comes a point where you realize that it's not just developing cognitive abilities. Your motivations and perspective change as well. It's not just you doing meditation practice. The practice is also working on you. Eventually you are going towards direction where you don't want to go and it can create lots of negative feelings, including fear and hopelessness (sometimes called the Dark Night of the Soul). This is the end of the road for many people. They lose the interest and do something else.
I think it's easier for people of religion because they have innate trust that everything is going towards something better and others have done the same.
It sounds like you're saying that moderate meditation is overrated, and more intense meditation is outright detrimental in the long term. That is surprising to me. Is this an inevitability? Did you experience this, and how did you push through it?
And of course, there is probably something behind that too, of which I have no idea.
Apologies for chiming in, but the simple answer is that "you" can't. That is, if you believe that there is a "you" that can push past this barrier, then you will fail. It's an impossible task. Where you go after that realization is up to "you." ;)
Short therm meditation experiences are mostly overrated. I think even little a day regularly 20-30 minutes has good effects if you make it a habit that you don't give up.
Can you elaborate on this?