Do you think there is an ETF and Index Funds Bubble which is happening as more passive investing gets more attention?

John Bogle himself has agreed that it will be dangerous if everyone was passively investing and there was no price discovery.

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The issue now is not so much with the large cap companies but the smaller cap ones where they are packed like CDOs that you are referring to. Now it's not an issue as long as they can sustain their debt and grow. The problem comes when investors constantly pour money passively into these pool of companies when they aren't generating any growth and instead just losing money without even a revenue growth. To make things worse, they may be highly leveraged and unable to sustain their debt.

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Whether we will see such a widespread passive investing bubble or not, nobody will know but certainly isn't there yet. Majority of people in the world aren't even investing in equities and there is still a lot of money flowing in and out.

Some thoughts on this: is the proportion of derivative used in passive index fund (monitoring s&p500) increasing or is it regulated to be capped at a minor.