Like I've said elsewhere, this is "for better or for worse," depending on your political sensibilities. Again, I think Tor is a good example here. Lots of CP on Tor, or so I hear. But also persecuted journalists and whistleblowers, and safer drugs than you'd find on the streets. You can't realistically say "I want X to be outside the reach of tyrannical governments, but not Y." It's an all-or-nothing deal. By its very nature, these sorts of libertarian technologies will attract all the illegal parts of society -- for better or for worse.
Having used both defi and traditional financial infrastructure, defi definitely feels a lot, lot more frictionless to me, at least while acting within the Ethereum ecosystem. Time will tell, but I find it hard to believe such frictionlessness won't eventually force its way into the world.