Because of CryptoBridge closing down
OpenLedger has shut down their gateway until the 15th of December.
Which means most of BitShares is shut down.
Sure, you can trade inside, but if you can't get anything in or out, its pretty useless.
You can still withdraw to STEEM, as RUDEX is still functioning
but there is very few on-ramps or off-ramps left.
https://dex.openledger.io/news/openledger-dex-temporary-suspension-of-activity/