I don't think you're appreciating what it would be like.

Sure, at first, the peacefulness of absolute sensory deprivation would probably feel pretty relaxing.

But then, it never ends. An eternity (or as long as your brain was kept alive) of nothing. You see nothing. You hear nothing. You feel, taste, and smell nothing.

If you're lucky, you'd start building a fake reality to imagine yourself in, like a dream. Over time, maybe you'd accept this reality as being real. People that lose a sense such as sight often gain an enhancement in another sense such as hearing. Maybe with the loss of all senses, the brain's imagination could gain more power.

Maybe it wouldn't be that bad, after all.

I thought maybe looking into how people in comas experience their time, but apparently it's common for them to have experienced much of what happened around them as a hazy dream[1], which means a lot of sensory input was still being processed. I'm not sure what it would be like to actually lose all sensory input. There's probably some disease that causes this, so maybe I'll stumble on it eventually, but even then we'll only get answers at this point if it's reversible...

1: https://www.quora.com/What-was-it-like-for-you-to-awaken-aft...

I put my money on the brain adapting to the absence of those inputs.