One dude with an LLM should be able to write a browser fully capable of browsing the modern web or an OS from scratch in a year, right?
Chrome took at least a thousand man years i.e. 100 people working for 10 years.
I'm lowballing here: it's likely way, way more.
If ai gives 10x speedup, to reproduce Chrome as it is today would require 1 person working for 100 years, 10 people working for 10 years or 100 people working for 1 year.
Clearly, unrealistic bar to meet.
If you want a concrete example: https://github.com/antirez/flux2.c
Creator of Redis started this project 3 weeks ago and use Claude Code to vibe code this.
It works, it's fast and the code quality is as high as I've ever seen a C code base. Easily 1% percentile of quality.
Look at this one-shotted working implementation of jpeg decoder: https://github.com/antirez/flux2.c/commit/a14b0ff5c3b74c7660...
Now, it takes a skilled person to guide Claude Code to generate this but I have zero doubts that this was done at least 5x-10x faster than Antirez writing the same code by hand.