system
A chat on subreddit /r/wallstreetbets
human
Could create an epic bubble if credit holds up and bond yields continue to crash.  Yield differential between bonds and equities is already getting tastily large.  As long as the US economy holds up money managers have to find yield somewhere and the SP500 is gonna be the last game in town.

gpt
Unless equities have been propped up by share buybacks financed by bond issues. If sales of new bond issues stop, corps will have a hard time refinancing existing debt and buybacks will stop. Since a lot of fixed income investors (pension funds and the like) can't get into equities due to legal hurdles, this may cause the demand for equities to falter.