It's not looking good for Tether, or Bitfinex for that matter whom they're affiliated with.
Let's start with a short recap of what's happened within the past few days.
The relationship between Tether and Friedman LLP who was auditing them has dissolved. https://www.coindesk.com/tether-confirms-relationship-auditor-dissolved/
The CFTC, a U.S. regulator has subpoenaed both Tether and Bitfinex https://www.bloomberg.com/news/articles/2018-01-30/crypto-exchange-bitfinex-tether-said-to-get-subpoenaed-by-cftc
In the past 48 hours since this news has been released, the market capitalization of the entire crypto market has dropped from $598 Billion USD to $498 Billion USD.
Pretty much all markets are now in the red over a 24 hour period, on average down by about 15%.
But hold on? Why would the entire market crash because of Tether? It's not even a 20 top currency, most people don't own tether, and with all the tether FUD going on, even more people won't go near it with a 10 foot pole. The printing of Tether has been known to be largely contributing to increasing the price of BTC over the past 6+ months, for reasons I won't get into here. Tether is actively traded on most major exchanges that offer a decent amount of altcoin (Binance, Bittrex, Okex, cryptopia) that use Tether in lieu of real USD. As tether goes belly up, there is likely to be a run on these exchanges. People convert their altcoins to BTC/ETH on these exchanges, pull their coins off the exchange and trade for real USD on real exchange that doesn't offer tether but actual USD like Bitstamp, GDAX, or Gemini.
This is already happening right now, and will likely only get worse over time. There's been an incredible amount of bad news regarding tether over the past months, and it's only ramped up in the last week. Is holding a big bag of crypto worth it at this time? It's been speculated the market will drop 50-80% as a result of tether's demise. It's just not worth it given the potential upside.
We're still at November 2017 prices. It makes this an opportune time to get out of the market, and get back in at a later date (in the next few weeks, or maybe month or two), after tether has collapsed, and those who have been defending tether have been proven wrong.