> Either way, your same argument can be made against the whole internet which should demonstrate how silly it is.

Not really.

I recognize that the same criminals can also use the wider internet too, however there are central authorities and regulators in different countries that have laws that regulate the internet in the countries that they are in and these criminals will be caught very quickly if they tried.

The difference is that Tor only makes it more harder to trace, hence the appeal to criminals, extremists and terrorists to use it for their illegal activities which that is its unintended use case after promising 'privacy' and 'anonymity' for 'everyone'.

So yes, that is it's 'decentralised' road to hell indeed.

You could have said the same thing circa 30 years ago regarding the internet versus phone calls and letters.