"I think investing same money in ... startup will be worth more"
You are correct on a micro-level but there are also macro-level issues when capital and rent (rent of money) are tied up in non-productive assets. An individual who buys a $1M house cannot put that $1M into a startup, but also on a societal level a bank that loans $100M of mortgages cannot loan that $100M to build infrastructure or a new manufacturing plant or a (large) school. So high price of non-productive assets hurt the macro scale as much or more than it hurts micro scale. Its very bad for the economy when the best thing to do with a pile of money is buy something that doesn't produce anything or grow anything. Its as bad economically as stuffing the money into a mattress.
> on a societal level a bank that loans $100M of mortgages cannot loan that $100M to build infrastructure or a new manufacturing plant or a (large) school
As a technicality, the whole point of modern banking is that banks can loan out the same money over, and over, and over again.
There are limits to that of course. Aside from that, I don't think it changes the bigger pix that "everything" involved in making a non-productive capital investment is unavailable for productive investments. Can't build a rail line thru there, can't that wood and stone into an office building. All that energy and labor invested, you're never going to get a return on that.
I'm not saying a world devoid of art and fun is a good goal, but am saying that going way overboard to one extreme is going to result in blowback.
You are correct on a micro-level but there are also macro-level issues when capital and rent (rent of money) are tied up in non-productive assets. An individual who buys a $1M house cannot put that $1M into a startup, but also on a societal level a bank that loans $100M of mortgages cannot loan that $100M to build infrastructure or a new manufacturing plant or a (large) school. So high price of non-productive assets hurt the macro scale as much or more than it hurts micro scale. Its very bad for the economy when the best thing to do with a pile of money is buy something that doesn't produce anything or grow anything. Its as bad economically as stuffing the money into a mattress.