at this point I am surprised when anyone has never heard of bitcoin. I am not surprised an economist would not know how it works and upon learning not be interested.

I don't necessarily think the concern comes from a conflict between centralization vs. decentralization as much as it is a gut reaction based on governments historically trying to control these things. That was my gut reaction when I first heart about back in like 2012. Someone was telling me the exact things you were probably telling your colleague and I just thought it was too risky to get involved. The government will figure out how to regulate it. Granted, I was a super poor grad student at the time so losing any amount of money would have been a big deal.

I ignorantly kept those opinions for a long time. Honestly, part of me was hoping my 2012 self would have been right so I wouldn't have to regret not investing back then.