My entire adult life there is a 10-15 year bubble. The first was savings and loans of the 80's, followed by Milken and junk bonds . The term "junk" wasn't a warning? Derivatives is a flashing red light warning for any investment.

Investor cults. Bernie Madoff didn't ask you to drink Kool-Aid, just give him money.

How many "dot.com" busts have robbed billions from investors.

Sub-prime mortgages? See 80's savings and loans and "The Big Short".

Crypto. It has elements of all the busts since 1970 and a common thread of those who get a % of the deal corrupting free market enterprise (inflating the price.)

It is really scary now because there is market manipulation happening. See GameStop!

The best investment? Target reitrement funds in your 401(k).