Maybe that's simply because you are older now? Sorry.
More seriously, I suspect this is mainly an artifact of how we currently perceive every form of human activity from a purely economic and commercial perspective. That automatically renders invisible any form of culture production that is not obviously commercially relevant today. Historic subcultures remain visible if some of their aspects had time to get exploited commercially.
And it's easier than ever to find books in non-traditional form or with non-traditional content because it's nowadays possible to publish decently made books for minority audiences. A credible path to commercial success is no longer a precondition, as long as someone is willing to pay for publication (but of course the visibility issue still applies).
More seriously, I suspect this is mainly an artifact of how we currently perceive every form of human activity from a purely economic and commercial perspective. That automatically renders invisible any form of culture production that is not obviously commercially relevant today. Historic subcultures remain visible if some of their aspects had time to get exploited commercially.
And it's easier than ever to find books in non-traditional form or with non-traditional content because it's nowadays possible to publish decently made books for minority audiences. A credible path to commercial success is no longer a precondition, as long as someone is willing to pay for publication (but of course the visibility issue still applies).