I would have been quite happy to use my own brain as the computational substrate and I had more than a few other people keen to be the input and output parts of the system.

It's rather unfortunate that in the West it is impossible to get elective brain surgery. The countries that will do it have at best a spotty record. I talked to someone who had it done in Brazil and their electrodes became dislodged after a few months.

There is nothing new or horrifying about self experimentation. Newton for one did it in conditions that were far more dangerous: https://psmag.com/social-justice/newtons-needle-scientific-s...

I'm totally fine with consensual human experimentation that somehow threads the needle around exploitation of the poor - just not sure how we do the latter part short of requiring experimentees to pass a minimum net-worth threshold?