Yes. I've used them. I have used it beyond the point of it hallucinating.

I am also a software engineer and have deeper understanding of how these systems work than your average user.

The software community tends to approach these things with more caution than the general population. The media overblows the capabilities of these systems.

A more concrete example is autonomous vehicles which were promised for decades and even now with a form of them on the road, they are still closer to remote controlled vehicles than the intelligent self contained systems we have been promised.

The difference between predictive text on a smart phone and predictive text of an LLM is my smart phone is predicting what I am likely to type next based on things i have typed in the past, while the LLM is predicting what comes next based on a larger body of work from source pulled from all across the internet. The LLM is then tuned by humans. This tuning step is under reported.

The LLM is unable to determine the truth of its own output. I would argue that is a key to claiming intelligence but determining what intelligence means is itself a philosophical question up for debate.

It's not really "intelligent" though, as in it's not thinking about what it's doing. What AI will do very well is reproduce jargon, and if it's jargon that we associate with intelligence then it appears intelligent. Academic papers for instance it can do a very convincing job because that format is so repetitive and jargon heavy.

You can do an experiment by asking it to produce a positive review of something niche and academic you're familiar with, then ask it to produce a negative review of the same subject. It will produce convincing dialogue for either scenario, but it does not know which is more true/accurate, and it will come across as a student writing about something they didn't do the reading for.

The "question if humans are [intelligent]" is the more relevant thing here. We're constantly expected to communicate with thoughtlessly reproduced jargon, and many of us can do this very well in a way that gives the impression of intelligent thought. The fact AI can do this, and that people are concerned about how intelligent it appears, is more a reflection on how derivative our notions of intelligence can be in these settings.

The fact that you believe an LLM is "intelligent" tells me you have no clue how they work and your comments on the matter can be ignored.