Earlier quoted context omitted.
That makes NO sense at all and I continue to be surprised at the fundamental misunderstanding of the US tax system by techies (it's really not that complicated for individuals). You pay tax on the GAINS, not on the value of the trade. If he owes the IRS $50k, it means he has a realized gain of ~$333,000. Where did that money go? The only possibility here is that he took $330,000 and reinvested ALL of it into 'altcoin…
It does make sense. I buy Bitcoin at $1000 in March. I trade my Bitcoin for Ripple in December when Bitcoin is worth $20000 and Ripple is worth $3. I have $19000 in gains because that is a taxable event. Fast forward to April and my $20000 of Ripple is now $3500 and I owe about $9000 in capital gains taxes. Even if I sold everything I can't cover what I owe because the losses on Ripple are in the next tax year and no…
It's not. It's just highly improbably and extremely imprudent.
Alternatively, his altcoins bounce back up, he sells them and this time pays the tax properly.