But be careful on that "tanks" part. If it really tanks, there might be a whole lot of people trying to catch knives.. And that could be real bad indeed.
It's a plausible scenario anyway - although strongly differing views on the probability.
Always amazed that some fail to grasp this, tether disintegrating is a solid buy for bitcoin, apart from the bad media coverage, which going by current standards has no effect on price. So that's $600m desperately trying to get into bitcoin all at once, this likely happening within a space of ~72 hours, think about it for a moment.
Would a crash of tether be a source of concern for the value of Bitcoin? If bitfinexed hypothesis is correct, that is to say that Tether is printed out of thin air and used to buy Bitcoin thus artificially inflating its value, then yes, absolutely: a crash of Tether would cause massive distrust in the entire crypto space...
Also remember this saying: "Don't catch a falling turd."
People have had cheaper alternatives to Bitcoin for a while now (ETH? LTC?) and yet BTC is still valued significantly higher. There’s more to this game than a cheap digital payment.