If you receive a donation through the Ethereum anonymization contract Tornado Cash, everyone can see that and since the contract is also used by sanctioned states like North Korea, all funds going through Tornado Cash were put on a sanctions list (pretty easy since they only needed to sanction the contract address). Monero is different in the sense that it has privacy by default and while you might be able to point out that some criminals use Monero, you can't really prove it directly with the blockchain like you can with Tornado Cash.
Imagine the government sees that a ton of people, including known terrorists were all sending credit card payments to the same guy, who mixes everyones money together to hide it's origin (now he is the origin though) and now money from that place of origin is used to fund attacks on the government but also to donate to kids with cancer. Of course the guy will have to be arrested and all the money that went through him marked as sanctioned.
Monero on the other hand works as an independent version of cash, not tied to any nation but instead governed by cryptography and code, which are protected by the First Amendment. If a government doesn't like Monero, they can still easily make access to Monero very complicated via laws that prevent centralized exchanges from listing it, and they do, but outright sanctioning the whole network could be very, very hard and might literally be impossible without trampling all over free speech laws.
If that is actually the case, the crypto portion is at least not that bad. The 10k limit on cash transactions is just not feasible in some industries though.
Just to make things clear, the Bitcoin ledger is entirely transparent so not actually anonymous. While it's technically possible to not get caught with bitcoin, it requires a ton of extra effort and if you mess up only once, you might retroactively link everything back together.
In Monero there are some known attacks that could reduce your privacy but if you are aware of those they can be easily avoided. There's actually a whole youtube show on those.
Imagine extorting $50k from someone, you can see the bitcoin move from the extortionists wallet to a non-kyc instant exchanger and 30 minutes later a non-kyc instant exchanger sends $50k minus transaction fees to a Binance account. Doesn't exactly require breaking encryption that's been around for years to make the connection.
Doesn't really matter though. If he had held onto the Monero, he would have still gotten caught because he accidentally uploaded his /home directory with personal info and published it with his extortion-account when trying to upload stolen data.
There are a few approaches how marketplaces can be handled. If you want it to be truly p2p and trustless you might want to look into an overcollateralized model like the one used by the particl marketplace. Regular reviews without further authentication can be faked very easily for example by sellers "buying" their own stuff from sockpuppet accounts and leaving good reviews.
If you receive a donation through the Ethereum anonymization contract Tornado Cash, everyone can see that and since the contract is also used by sanctioned states like North Korea, all funds going through Tornado Cash were put on a sanctions list (pretty easy since they only needed to sanction the contract address). Monero is different in the sense that it has privacy by default and while you might be able to point out that some criminals use Monero, you can't really prove it directly with the blockchain like you can with Tornado Cash.
Imagine the government sees that a ton of people, including known terrorists were all sending credit card payments to the same guy, who mixes everyones money together to hide it's origin (now he is the origin though) and now money from that place of origin is used to fund attacks on the government but also to donate to kids with cancer. Of course the guy will have to be arrested and all the money that went through him marked as sanctioned.
Monero on the other hand works as an independent version of cash, not tied to any nation but instead governed by cryptography and code, which are protected by the First Amendment. If a government doesn't like Monero, they can still easily make access to Monero very complicated via laws that prevent centralized exchanges from listing it, and they do, but outright sanctioning the whole network could be very, very hard and might literally be impossible without trampling all over free speech laws.