Buybacks are dividends by another name.

But in that case, you do have to sell to get any cash out, so "never selling" is similar to reinvesting dividends.

Why would I want someone creating taxable events for me? Under the current tax regime, buybacks are vastly superior.

As long as you have an accurate sense of the intrinsic value of your shares at any given time; there is a price at which buybacks destroy more value for continuing shareholders than they would lose to taxes on dividends.

Speculate isn't the right word to use for Berkshire's investments.