Remember, we are talkin about a bunch of good, well supported engineers working within rather well oiled machine with a lot of other teams doing similar work and sharing experience and advice.

Nobody said it is good general advice. There is so much stuff you need to do well to have a good chance at successful rewrite that it become good advice that it is a bad idea. Nobody said rewrites cannot be done. If you have a company that knows how to do rewrite (and makes it constantly which, I guess, helps a lot) then a lot of problems can be solved by starting from scratch and it it may be it is well worth it.