If the main issue with them is lack of galvanising then i dont suppose those kind of issues will show until the car is over 5 years old. I fully admit its a very valid concern. The main point of EVs is they are better environmentally, but this is absolutely not the case if penny pinching a few hundred quid on manufacture costs means the cars are fit for scrap at 10 years old because of rust.
Mud sticks as well. I had a 1998 fiat. Fiat were (according to the main dealer and i havent fact checked) the 1st mass produced car company to galvanise their car bodies to stop rust, but even so, even now decades later they still have the reputation for being rust buckets even tho it isnt the case any more.
but that reputation earned in the 1980s is still their to a degree.
I think today though it's super rare to see cars over ten years old, and most will be bought on pcp cars are becoming more and more like phones.