To be honest, the case of Paradex is the first I have ever heard of. Paradex is a decentralized Exchange based in the United States but presently, Paradex has been acquired by coinbase. It now offers even better services more than it used to. Paradex can be used as a payment system and also as a medium for trading one cryptocurrency for the other.
Secondly, I also found out that coinbase acquired Paradex in order to expand its platform to offer better services. I don't rate Paradex as a dead Exchange since it is still available but no longer in the form it used to be. The main aspect of Paradex I used to access most was its peer-to-peer trade service but I now use coinbase. In conclusion, Paradex website is no longer for Paradex because even if you try to visit, they will airt you to coinbase.