My mental model has been 3D computer graphics: doubling the polygon count had huge returns early on but delivered diminishing returns over time.
Ultimately, you can't make something look more realistic than real.
I don't know what the future holds, but the answer to the question "can LLMs be more realistic than real" will determine much about whether or not you think the curve will level off soon.
The equivalent bar in this domain would be human intelligence, and we already have growing lists of tasks where machines outperform humans.
We even known of natural systems that outperform humans on some metrics, e.g. bird-brains have higher neuron density than ours because evolution had to optimize more for weight.
In 3D graphics there's diminishing returns on investment for the technology itself, but the real limit is one of economics. How to create all those assets required by the rendering tech, and make your money back. Preferably while also keeping your customers interested long term, by not becoming risk averse.
In the same fashion, LLMs have to pay for themselves to keep the trendlines going. In a whole-systems -sense, mind, not "$2000/month is cheaper than hiring a developer" while the rest of the economy collapses.
My mental model has been 3D computer graphics: doubling the polygon count had huge returns early on but delivered diminishing returns over time.
Ultimately, you can't make something look more realistic than real.
I don't know what the future holds, but the answer to the question "can LLMs be more realistic than real" will determine much about whether or not you think the curve will level off soon.