There is a category of car, where the buyer identifies with a group. They don't buy the car for price or service record; they buy it to join a club. The VW Beetle; the PT Cruiser; Cooper's Mini all are cars like that. It doesn't matter what resale value they have, or how often they break down. All that matters is the self-image of the person doing the buying. They go into it knowing they will like the car, no matter what. So the 97% number is entirely expected.
CR didn't say the car wasn't good, they said it wasn't reliable. The car performed very well on their tests related to the road; so it is fun to drive, safe, comfortable, etc.
The problem is that it breaks; and then you need to get it fixed. It seems Tesla is pretty good about fixing things without giving you trouble about it; so they make the negative experience into a positive/neutral one.
This leaves you with a good car, not reliable, but still with happy owners; so everything makes sense to me.
And the stock overreacts to all kinds of news, and it is true that reliability will matter as far as their future profits (if they keep everyone happy it costs a bunch; if they don't, they'll lose sales).
I imagine it all still goes through DDG, so it would be very difficult for Yandex to disambiguate more than a short stretch of a stream of search queries (let alone associate them with a person) even if they wanted to.
There's still the issue of individual queries revealing something that the user doesn't wish revealed. It would be interesting to see how exactly DDG uses these other search engines as sources (and if they are able to make demands with regard to logging), but it's worth noting that DDG logs search queries itself (just not associated with a person), so that may not be possible to ask for.