there are plenty of people who basically believe this is the end of the human economy - there will be nothing left that isn't done by AI in the future. Even the bits left that humans do will be human facades on AI driven activity (like your hairdresser will be viewing you through AI powered glasses using AI powered scissors etc).
So from that point of view you can indeed look at it as the entire value of the economy should be invested into AI companies.
That is ultimately where it is headed and has been headed for over 100 years now.
The question is when will we get there.
If the answer is tomorrow, money means nothing and none of these investments matter. If the answer is 30 years, well lots of money to be made up until the inflection point of machines being able to design, build, and repair themselves.
But let's be real, the AI output today is largely complete and utter shit. Like, really, without careful promoting and oversight, it's not fun to read, it's not smart, it's not accurate, it's not thorough, and it's certainly not yet over the massive show stopping hurdle that is lying and hallucinating all the time.