Assuming you lived through those cycles, can you tell us why?
I really cannot wrap my mind around the idea that LLMs will just not be a part of everyday life in the future — in tech and everywhere else...
1. We will (hopefully) eventually get back to the truth that programming (for problem solving) is about understanding and modeling the problem space, not writing text that satisfies a compiler / runs an app / appears to work like well-written software most of the time. And programming (for art and creativity) is about the human spark of creating something outside the norm, informed by life experience, relating to another human because of the shared experience of being human. I believe that this will shake out in the end as these tools at best helping us to think about how to write software, not actually writing the software themselves. So in that sense, we will get back to "how we were writing code in 2019" — using tools to help our own brains create.
2. The now-long history of the internet has proven to us that those skeptical of trust in what is on the other end has largely proven out. Not commercially — we can almost entirely trust what is on the other end of a business transaction, at least when trading with large players in the economy. Some costs there include compromised online identity and compromised financials (from repeated, rampant data breaches). But we can't trust the voice of individuals anymore, as proven by our rapidly disintegrating democratic norms. We are in a crisis point as a civilization when it comes to not actually talking to each other at a human level anymore, rather being mediated by the internet. So that's where that — the internet never going away — landed. I think the jury is still out on whether the internet is good for humanity. I'm not saying it will ever go away — it can't possibly — but the fact that we've accepted it as inevitable has led to us failing at considering possibilities for reigning some things in or keeping some things offline. As a present example, we now purport to trust closed models run by trillion dollar companies, when one poll showed one in five voters asking chatbots who to vote for in a few weeks in the US elections — no chance for corruption there! "How we were writing code in 2019" was being aware of where the code and algorithms we were using came from and (even in the worst case, of secreting code into a large codebase via theft) trusting it as doing as its author, a human, intended.
3. Like other cycles, unsustainable economics are propped up right now by institutional investors riding numbers-go-up until the train crashes, always looking and finding someone else to point out and say "but they're still onboard" — just like past cycles. The common person / worker / individual will be left holding the bag in very painful market convulsions that will forever scar those who actually make it. There's a cost there — ruined lives, careers, potential — a cost that we repeatedly decide is acceptable. "How we were writing code in 2019" was weighing the tradeoffs of using a product or voting with our money on its sustainability, rather than determining the future laid out by us (not at all by random or by merit) is inevitable and "the way" that we should pursue. Groupthink at its worst.
I am using "How we were writing code in 2019" here not as a point that we should return to, but as the point before the hype took hold and all reason was thrown out the window and a point to consider as we weigh — really weigh — the pros and cons.
Lastly, on a personal note, I've got no fear of being replaced. Like another in this subthread, I happened into a career that paid well for doing something I already loved. At times in my career, I even chose the path that made the least sense financially, in order to pursue something I loved and that satisfied my curiosities. I am extraordinarily fortunate to truly love the art and craft of programming and to work with beautiful, caring people who hire me to do so. If it goes away tomorrow, welp... it's been a good run.