It's more than the past couple of years, steady improvements in machine learning stretch back decades at this point. There is no indication this is stopping or slowing down, quite the contrary. We also already know that better is possible because the human brain is still better in many ways, and it exists.
You can claim that continued progression is speculative, and some aspects are, but it's hardly "an article of faith", unlike "we've suddenly hit a surprising wall we can't surmount".
> steady improvements in machine learning stretch back decades at this point
Except that's not how it's actually gone. It's more like, improvements happen in erratic jumps as new methods are discovered, then improvements slow or stall out when the limits of those methods are reached.
And really, there was a version of what I'm talking about in the shorter timespan with LLMs - OpenAI's GPT models existed for several years before someone got the idea to put it behind a chat interface and the popularity / apparent capability exploded a few years ago.