What is great is finding a reliable counterparty through a P2P trading platform and just using some chat/messaging to arrange subsequent trades.

The problem for Vexl and others is that these services then don't get fees for these later trades, even though they had done the initial matchmaking. And worse, these platforms show less liquidity because you then have your trusted trading partners on Signal or whatever and aren't posting trade offers at all anymore. Without that liquity, others looking to do their first in-person P2P trade(s) get frustrated as there are few offers that remain and the rates offered are not that great.

So the platforms themselves never reach all that high levels of trade volume, nor liquidity in the offer books.

But it all still works, somehow.