I don't have answers to all of your questions. I don't know where the current wave of AI will go, or what jobs it might eliminate. I have gone through one "AI winter" already and multiple popped bubbles and supposed threats to my career. The hype and expectations have never matched the reality.

Because developing software costs so much money, and requires taking a lot of risk -- because software development lacks the predictability and repeatability of "real" engineering, see my other comment -- corporate executives are always looking for ways to reduce those costs and get something they can plausibly call "working software." Those execs have tried no-code/low-code several times. COBOL and SQL both promised end-user coding, with the usual result, because learning a language is the easy part of programming. Offshore outsourcing made a dent for a while but demand increased faster than supply of programmers, and now the offshore places have their own domestic demand for programmers. The current thing is LLMs, what we're calling AI these days. The VCs and companies who have a lead and a lot to gain are selling a big pile of hype to corporations. And some of it may work, I don't know. Based on history I expect LLMs to displace people in lower-end rote jobs, and that will likely include at least some of the easiest kind of programming. If VSCode can write 75% of the code for you and underline the errors an LLM can probably do even better.

I started in my career in the late '70s, and have stayed consistently employed since then. I never planned to make programming a career (I studied history at school and my parents hoped I'd go to law school), but it was challenging, came natural to me, and paid really well, so I've stuck with it (and now I can't do anything else to make a living). But I can't really put myself in your shoes, or relate to the OP's concerns except in an abstract way. I don't apply for jobs or go through hellish (and useless) interviews, although I read about those. I don't see LLMs taking over my job in what's left of my working years, but I suppose it could happen.

I'd like to tell you to sit out the hype cycle, the AI/LLM bubble will burst, the hype won't turn into a workplace revolution, the jobs will come back. I don't know that for sure but that's what I would bet on. But that doesn't do you or anyone else any good, looking for a job today, in a terrible job market full of recently laid off people who have at least some experience and (if they paid attention) some professional contacts.

Friends and professional contacts -- real people I know, not connections on LinkedIn -- have always worked best for me, so I advise meeting people and making friends, both in tech and in other fields. I have got some surprise job leads and freelance opportunities just chatting with people. I make it a habit to talk to strangers (to keep my natural shyness in check), you can try that. Word of mouth really works. If I had to find work today I would be talking to everyone I know, people I worked with 20 years ago, not filling out online job applications. I understand that's harder for someone without a lot of work experience.

As I wrote in my original comment, employers always need people who can solve business problems and add value. They don't always need more programmers. Figure out how to present yourself as a person who can solve problems, figure things out, work with the organization, add value, and you will find jobs, because people who can do that are always needed. It just isn't that rare anymore to have the ability to crank out web app code, and LLMs will make that meager skill even less valuable.

If you can speak and write effectively people will tell you, I guess that's the benchmark. If you can keep someone's attention, persuade someone to change their mind, communicate your skill and see someone use that knowledge, that's effective. You certainly can learn to speak and write better. Try joining Toastmasters to get over fear of speaking to groups. Watch videos of good presenters and speakers, or go see them in person. Read books about good writing, read novels that have held up for a long time (classics), and read essays and books by people who love reading and writing (Umberto Eco comes to mind). Go to writing classes and workshops.

Communicating well, and having the ability and knowledge to talk about more than one thing, will make you more appealing to other people, including potential employers and customers. I have freelanced for over ten years, and the number one thing I hear from new customers -- almost without exception -- is how the last people they hired stopped communicating with them. It doesn't take much effort to acknowledge and answer an email or call, but too many people fail even at that.

I like to say that maybe there's no such thing as the 10X programmer, or the 10X communicator. But you can easily observe that most people are at 0X or just barely above that. Be at least the 1X, worry about 10X later.

As for fundamentals, I don't know how to show that directly. A lot of it comes from practice and mentoring from more senior people, at least in my own experience. I'll repeat that if you can solve actual business problems and add value you will have a big advantage. You show, don't tell. Knowing the fundamentals will let you show and perform with confidence because you will see the same problems over and over, and if you already know how to approach the problem your employer or customer will understand that you know the fundamentals.