As long as the sources are adding information for someone who wants to learn more about Bitcoin and it's not corrupting the mind of its readers, that's a fine source.
These sources are even just for free and they've made of course by these exchanges or whoever sponsors them and have it put on their website. And that's the actual fee that every guest or visitor pays them, the traffic in exchange of the resources and information that they've included on these articles.
But it's true that some of these articles might be misleading and bias.
They might be misleading due to some misconceptions that authors viewed from bitcoin. This is why we don’t have to limit ourselves from just few articles and stick to them. There are a lot of reputable and legit resources that we can find online, we just have to explore the internet and do our own diligence to find out which are legit and which are unreasonable. Thus, exposing our minds into different views make us more knowledgeable and wise.
With various resources that we can find over the internet, it's true that no one is limiting us to have a lot of source for articles that we like to read.
When something is off with the information that's said on that particular article that we read, we can find another one that's more verifiable and reliable.
Fake news is a lot these days and you can also read a lot of articles that's made for an agenda that's setting the mindset of readers depending on the perspective of the author.