You likely don't actually want an AI that learned only from your business documents. Imagine the equivalent of this in a person: someone who only consumes your wiki, no news, books, TV shows, games, conversations... Such a person would get "overfit" to the wiki, lose the ability to think rationally, and probably end up in psychiatric care.

We assume that weights need to be continuously updated because that's how lay people imagine the human mind to work. But even the human mind (most likely) doesn't learn continuously: there is a consolidation process that happens during sleep.

So in some sense AI learning is already not that different: latest data from short term is consolidated into long term memory. It's just that for a person this happens nightly and for an AI - quarterly. And the short term memory is that person's experience vs the entire Internet.

And whether something is lucrative or not is decided by utility and price, not how the technology is put together.