I don't have Netflix, so I 'm not clear if the rating shown to users is changing. Or does it not show a rating, just use it to decide what movies to surface for you?

In any case, simplifying the ratings users can bestow makes a lot of sense, unfortunately. We like to imagine people carefully considering the merits and flaws like a professional reviewer, but the fact is that the vast majority of users only ever use two ratings anyway: if they like it, 5 stars; if they didn't, 1 star. There's maybe a third option where if they're ambivalent they just don't rate it.

So star ratings aren't actually very useful for evaluating products. This xkcd https://xkcd.com/1098/ made me realize that an Amazon product which has a 20% chance of exploding when you open the box, and otherwise works normally but unexceptionally, is gonna average out to a four-star rating for a product you really shouldn't buy. I always look at the one-star reviews before buying stuff now, no matter how few of them there are; knowing a thing's failure modes is much more useful than a bunch of praise.