You are the same guy who created
a thread two years ago asking which method you should pick so the government cannot track you and you don't want to go to the jail. Why didn't you choose those non-KYC exchanges to clean your Bitcoin or send your funds to whoever you want? You yourself decided to use mixers and asked for help. You probably did not know about those non-exchanges, or the process is too long. Yeah, if someone can use privacy coins like Monero or Dash on exchanges and do it multiple times, you don't need mixers. But the Mixers have a good fanbase. We have Telegram does not mean whatsapp is useless.
Mixers make it much easier to obfuscate digital tracks so that a person's identity or personal data cannot be determined. In my opinion, this is a good tool that benefits those who want to remain anonymous when sending money. Who needs this? For example, opposition bloggers who have fallen out of favor with the government, as well as those who donate to such people.