While I essentially agree Musk is BSing, TAM doesn't imply "we can actually get this entire market". The TAM for the food sector is *all food*, not what one particular alcopop manufacturer can sell: https://en.wikipedia.org/wiki/Total_addressable_market
AI today can't do all desk jobs, I don't know how far we even are from that given the spiky nature of ML, but it smells like this IPO is using that as the justification for the claim.
The TAM of a particular alcopop manufacturer is "all beverages sold on the area it distributes". Misrepresenting it as "all food" would be borderline fraud.
The TAM for AI right now is the sum of all revenue from all AI companies. That seems to be something around $100B, or about 0.3% of the number on that document.
If they plan to grow that market, that's a different indicator.