Did you follow product development in recent decades? The iPhone was not ready for prime time as well but still people bought it and where very happy.
A lot of products nowadays are kind of MVP's or betas and people are willing to accept their flaws and edges just to be an early adopter of technologies which remind them of beloved Sci-Fi movies.
> by construction, it also cannot store information provided by the user for later use, nor can it "look up" facts
Other tools can do that. You can connect them just like you do with micro services or modular systems - what is the issue about this?
The statement "starting a business ... is a bad idea" cannot be proven and there are also no examples to strengthen this position. So until one does you just cannot prove this statement so this is just speculation.