White House Market made an announcement his week that states: Bitcoin payments are no longer accepted. The 3rd party exchange api we used (Morphtoken) has suddenly decided to block access from Tor exit nodes and while this is trivial to circumvent we decided to respect their descision. The Bitcoin workaround was supposed to be there just to help with transition to XMR and as we are concerned it's done, therefore we are now Monero only, just as planned.
Morphtoken provides an exchange service through which Tor users could easily exchange coins at the given rate without KYC. But lately it seems that their gesture to blocking access from Tor is to prevent criminals and darknet users indulging in illicit activities.
White House Market when launched only used Monero for payments and it was the only market that enforced Monero. But as the market growth increased rapidly, many users requested to add Bitcoin as a second option for payments. And upon the request, Bitcoin was added.
Now the market is accepting XMR only just as it was idealized.
A debate on whether to use BTC or XMR has been going on for quite some time, given that how vulnerable Bitcoin has become since corporations have stormed tracking tools which can easily unveil the transactions to exchanges linked to an individual's identity.
To darknet users its been clarified that Monero is the superior coin over Bitcoin when it comes to privacy. Some markets are also thinking to enforce Monero and discontinue the use of Bitcoin for payments.