No. Say you just made $1 billion in capital gains but you don't want to turn it into cash and pay taxes. So what you do is take out a loan of say $100 million against some of your securities, which gives you plenty of cash to play with. In fact you can keep doing this, just raising another loan to pay off the first one, and so on, until you die - at which point your estate can pay off the outstanding loan, and your legacy is exempt from capital gains taxes. It's called 'buy, borrow, die'.
Obviously I am over-simplifying a little, but this is a real thing. Here's a more comprehensive explanation: https://smartasset.com/investing/buy-borrow-die-how-the-rich...