The point isn't that the result from an LLM is particularly valuable. The point is that the advice that you get from your typical (management) consultant isn't particularly useful. And that's the only bar you need to clear.

There are basically two reasons for consultants:

Either you need some once-removed thing (be that you selling/buying some part to/from a competitor, accounting, lawyering). That part sensible people will not replace by LLMs. But here it isn't that you yourself lack the expertise at all. Here it is absolutely necessary, that someone else does the actual implementation.

Or you have some general "we need to do better" feeling. And here you have again two options: 1) you know _what_ your problem is and you just need the best solution there is. This is (obviously somewhat tongue-in-cheek) essentially corporate espionage. Again you cannot replace that with an LLM (or maybe you can I don't know), but you will pay a lot of money for it. Or 2) you don't know what the problem is. Now you are competing in finding an appropriate starting point with 20-somethings fresh from university that are not wanted in your organisation and therefore won't get access to the relevant information anyhow. So yeah, I'm willing to believe that the typical success rate of those consultancy projects is low to negative.

If you are only given a 3 week crash course in $BUSINESS, you won't be able to produce much more than a generic set of "have you thought about that?". And THAT is something that I believe LLMs to be reasonably good at. And they are dirt cheap and instantly available compared to any kind of human consultant.

Now I don't think that will necessarily a net-negative for consultants in general. I do think, similar to ATMs, that consultations are mostly becoming cheaper by that.

Thing is, most code is written by entry-level/junior programmers, as the whole career path has been stacked to start grooming you for management afterwards, and anything beyond senior level is basically faux-management (all the responsibilities, none of the prestige). LLMs, dirt-cheap as they are and only getting cheaper, are very much in position to compete with the bulk of workforce in software industry.

I don't know how things are in other white-collar industries (except wrt. creative jobs like copywriting and graphics design, where generative AI is even better at the job as it is at coding), but the incentives are similar so I expect most of the actual work is done by juniors anyway, and subject to replacement by models less sophisticated than people would like to imagine they need to be.