I'm well aware of how they're doing it. It makes sense to start with a mostly-automated rewrite, what they confusingly call a "port".

But after that step, the end result will be maintained and changed manually. It makes perfect sense to make improvements (including to performance) this way. All I'm questioning is the choice of target, since it excludes some possible future improvements. If you're rewriting (semi-automated or not), it's an opportunity to future-proof as well.

I don't understand why you're being so confrontational about mere technical disagreement.