Stock market offers liquid financial products, while angel investing is definitely illiquid. Irrationality in VCs will always be involved because we are human-beings but for sure less than in the stock market.
Totally agree with this! There's also the notion of sunk cost when it comes to angel investing, which often arise when a startup goes through a slow steady decline in profitability and eventually, to their ultimate demise. You don't (usually) see this happening in the stock market.