I am so curious that many people do not know or research properly about bitcoin and many other crypto assets, they only know little about them and dipicting them bad to people. Normally, there are two types of cryptocurrencies in term of psuedonymity and anonymity, they are:
1. The ones with public ledger which transactions can be seen by everyone on blockchain. Example is bitcoin
2. The ones that are are completely anonymous in which transactions are not designed to be tracked
I believe people that know about cryptocurrencies should focus on these while saying cryptocurrencies are used for for terrorism financing, money laundering and drug peddling. Although, pseudonymous cryptocurrencies can raise a concern but not like anonymous coins, that is why some exchanges are delisting anonymous cryptocurrencies, because their transactions can not be tracked.
where there was not crypto Funding for terrorism, drug peddling was not there? Govt can track fiat money still they can not prevent those funding. This is not about funding only if you can change the society there won't be any extremism. Only privacy coin could be the problem but for other types of crypto, I think it's better than fiat. Everything is transparent and easy to track.