This awful advice can’t be blanket applied and misses the point: starting from zero is extremely easy now with LLMs, the last 10% is the hardest part. Not only that, if you don’t start from zero you aren’t able to build from whatever you think the new first principles are. Spacex would not exist if it tried to extend old paradigm of rocketry.

There’s nothing wrong with starting from scratch or rebuilding an existing tool from the ground up. There’s no reason to blindly build from the status quo.