Also, I find putting rear window heating on in such heavy rain for a couple of minutes improves visibility a lot.Not on mine… don’t really miss it functionally. Don’t particularly care for it aesthetically.
Absolutely not needed. I have driven 10,000 km now in my Macan Turbo in rainy DK and never missed it.I've taken many cars without rear wipers on ski trips (plus I live in the rainy PNW) and it's always been fine. I think the rear wiper gets overrated.
Get ceramic/water repellent applied. My Rivian has a tiny little rear wiper and I've yet to actually use it.