> It's funny, but I think the article is showing it's age. It's no longer true.

Joel argues 2 effects:

# Developer & time-cost of a rewrite is a big unknown. That's still true, but LLMs may cut that down by a factor of 10x or more. You cut time & developer-hours by throwing tokens ($) at it. An optimist might say this cost has vanished.

# Shipping a rewritten product is -by itself- an unknown risk. That still holds. You can do all the testing you want, but your test suite != your clients environment(s? multiply by number of users or target platforms).

A single bug that pops up in the rewritten codebase (which wasn't in the old one) can hurt a vendor's reputation badly if the stars align just right.

All in all Joel's article held up pretty well (esp. given how long ago it was written).