If they do claim that, it's likely to be just pure nonsense designed to market their own businesses since they'd be the ones selling the AI solutions. In reality, replacing all your workers with machines will just cause the profits to go close to 0 due to what value is and how it works, there's no rewriting it as it'd be akin to rewriting something like what gravity is.

As to why, it's a bit complicated of a topic but essentially, value is the socially necessary labor hours required to produce something rather than being something subjective (if same quantities of gold and silver had the same value but gold required 10x more work to obtain, nobody would be mining for gold).

Production requires investment into constant capital (i.e. machinery, raw inputs) which, under average market conditions, are already essentially "priced in", they embody the labor hours already invested in them and merely transfer their own value over into the new commodity. During production, raw materials get used up, machinery wears out and needs to be replaced and so on.

Then there's variable capital which is the workers who are paid a wage, and is where profit comes from since wage labor allows capitalists to pay less to the worker than their labor produces, with wage essentially being a "subsistence fee" for the worker to renew their labor power.

If you remove variable capital, you remove the only reliable point in production that allows capitalists to extract value. Ofc, there's a chance that they can hit some bargain deal and get constant capital under market price, but it tends to average out as time passes, this can be seen right now with AI and the companies struggling more and more.