That's just ... not true? Have you tried qwen3.8 (compared to qwen3) or deepseek 4? they've improved tremendously, maybe not at every class of problems, but if you take a disciplined approach and don't ask them to one-shot everything (e.g. update agents.md as you go, actually use the thing you build, give feedback etc), it's positively absurd what you can get done now with a single agent.

I agree that not every class of software or problem or this or that is going to be decimated/revolutionized whatever, but to not see any improvement since 2025 just sounds like you're not looking.