Yes accountability especially in the US is lacking. But there is some, there are formal ethical codices (i.e. see NPR's https://www.npr.org/ethics), there is proper journalism training (see e.g. the Annenberg schools).
If you compare the US media to other nations, and especially if you look at them historically, they have been pretty good at this.
I'd argue that your standards are probably too high. Accountability is a shitshow and virtually nonexistent across the globe. It's a darn lucky situation if you even have some.
[edit due to reply limit]: Of course NPR is biased, what do you expect? There is no neutrality in things that human believe. The difference is having public guidelines, committing to them and listening to criticism That's accountability.
