I know its a few months old, but I wanted to add to this a little, because I'm wondering why no ones on the clearnet wants to use PGP? Yes proton and tuta both encrypt end to end, but what if a vendor or buyer has their password leaked somehow, and LE, Phishers, or scammers, get access to the their messages? Wouldn't it make sense to have all the sensitive matterial in your emails have an extra layer of protection? Most darknet vendors require you to at least encrypt your address and anything that might be able to identify or incriminate you or them, even if you're comunicating through a secure server like proton. So why do Clearnet vendors not adopt the same policy? I understand its more grey area here, and usually as long as its not being sold for consumption there is no arrestable crime, but why give them any evidence at all? Why give your customers the chance to say anything incriminating to begin with? Especially when PGP is availible to everyone for free, and not that difficult to use. Theres tons of tutorials on youtube, it took me about 15 minutes to learn and use, as a vendor you would cut out the "stupid kid" orders that will probably hurt themselves with your products or screw up your opsec, and you also gain the option of dark markets if you so choose. There doesn't seem to be a downside to me. I feel like if I was a vendor here, I'd require everyone to PGP encrypt their messages, in addition to sending through an encrpted email server, and using the self destructing message feature, and leave links to tutorials on my page. Any good reason not to?
Also, if anyone has questions about PGP, feel free to message me, I'd be glad to share what I know.