“In the earlier years, the answer is stupidity,” Mr. Buffett replied. But then Mr. Buffett added that his friendship with Mr. Gates has grown over the years, and he has stayed away from investing “because of the inference” that could be drawn.

And Amazon and Alphabet...

Mr. Buffett has famously avoided investing in tech companies because he didn’t understand them. But one investor wanted to know if Mr. Buffett’s stance is evolving. Beyond Apple, the questioner pointed out that Amazon and Google parent Alphabet have the characteristics of companies Mr. Buffett typically likes to invest in: strong brand names and little competition.

Here’s the reason Mr. Buffett gave for not investing in Amazon:

“The truth is that I’ve watched Amazon from the start, and I think what Jeff Bezos has done is something close to a miracle. The problem is if I think something will be a miracle, I tend not to bet on it.”

As for Alphabet, Mr. Buffett said that he had “made a mistake.” He said he was unable to conclude that at Alphabet’s present prices, its “prospects were far better than the prices indicated.”

He then explained that he didn’t invest in Apple because it was a tech stock. “I went into Apple because I came to certain conclusions about the value with which the capital was being deployed and about the ecosystem,” he said.

The discussion did lead to one of the more humorous exchanges of the meeting:

Mr. Munger: “I’ve been to Google headquarters. It looks to me like a kindergarten.” Mr. Buffett: “A very rich kindergarten.”

One thing Mr. Buffett and Mr. Munger aren’t fans of? Cryptocurrencies.

Warren Buffett and Charles Munger saved their harshest words for cryptocurrencies.

“Cryptocurrencies will come to bad endings.” Mr. Buffett said, responding to an attendee from Ukraine.

Mr. Buffett’s main argument against cryptocurrencies is the same one he has made about gold: They are not a “productive asset.” That means the value of cryptocurrencies is determined solely by what someone is willing to pay for it.

“If you had bought gold at the time of Christ and you figure the compound rate on it, it’s a couple tenths of a percent,” Mr. Buffett said.