OSHA uses A-weighted sound pressure to estimate hearing risk, which roughly follows the ear's sensitivity and gives low frequencies much less weight, much like Fletcher Munson curves. Check section 10 here: https://www.osha.gov/otm/section-3-health-hazards/chapter-5. So bass having more volume/power doesn't by itself mean it's equally damaging to the ears.

I also wonder about the opposite situation: someone turning the whole volume up because the bass doesn't sound loud enough, raising the other parts with it. Having the bass adjustable could help there. Some songs already have plenty of bass, so it makes sense to turn it down for those, and perhaps have a dynamic limiter when it gets excessive.

By "blocked" I meant the impression of music sounding too close to my ears, rather than my hearing feeling blocked after listening. Of course, feeling softer doesn't completely establish that it's safe either.

It's not a new fashion. In the 70s/80s hifi often had a "loudness" button which boosted highs and lows, although not as much as they're boosted by EQ settings today.

The more recent variant is "smiley curve" EQ - high at the extremes, drooping in the middle.

EQ can mess with transients, especially in the bass. You get more volume, but at the expense of some time smearing.