In the long run, it’s cheaper to defer those taxes and pay them with discounted future dollars. In the best of outcomes, the taxes can be avoided altogether.
Even so, there is such a thing as being too good at tax deferral. People who pay higher tax rates on higher income may see deferred tax bunching up in a manner that pushes their tax rates even higher.
And for those who are not already in top tax brackets, deferring income too aggressively can cause future tax liabilities to increase by more than the discounting benefit of deferring them in the first place. In such scenarios, it’s often actually better to take advantage of lower current tax rates instead.