BJ is a game with a great deal of variance. With a 150 unit BR, you can survive a negative swing of 20-25 units and still be playing when the positive variance kicks in. With a 20 unit BR, you will lose it all during that bad swing and not be around to enjoy the positive swing.
Take a coin flip. It's 50-50. After ten flips, or 1,000 flips, you should get results that are around 50-50. If you have $100 and bet $1 a flip, you should have around $100 after ten flips, after 100 flips and after 1,000 flips.
But what happens if you only have $1? Now you have a 50-50 chance of losing your entire BR.
The fewer units you have, the greater the risk of being wiped out.
