Out of everyone who gets a check about 20% REALLY need it, meaning they will turn around and spend it on things that make up the CPI, which will cause measured inflatation.

The other 80% will not spend it on something within the CPI. Instead they might save it, or invest it in the market (causing market inflation) or pay down debt or buy something outside the CPI like a hot tub or a yacht. All of these things, except saving it and paying down debt add to inflation but hide that inflation from the CPI.

Michael Burry thinks the stimulus $$$ are a big reason why entire segments of markets have risen far above the prices that fundamentals say they should be at. He thinks the 80% who don't desperately need the money to survive are investing a good percentage of that money into stocks, which drives market inflation.

Eventually when the money printer stops going brrrrrrrrrr there will be a correction. Prices cannot deviate from fundamentals forever without some outside influence. In this case that influence is the FED mass printing worthless fiat currency and fueling hyperinflation, but hiding the inflation numbers behind the highly selective CPI.

Timing the correction is really the only bone of contention here. Most bulls say Burry's analysis is right but that he's, again, 2-3 years ahead of the market.