Most book sites are recommendation bubbles where once you get stuck in one you only get recommended things that you've already read or that you are not really interested in reading. Breaking out of these bubbles is super hard. So, I can see how it is hard for new authors to break into these bubbles.
And then of course there is the notion that a lot of authors are not attractive to a broad audience; which means reaching such an audience is quite hard. Some of the stuff I read is pretty niche. Most of that is in English instead of Dutch (my native language) because a lot of that stuff just is a hard sell in the tiny Dutch market. Entire genres are excluded from being translated for this reason. E.g. most of Neal Stephenson's work has not been translated (except for some of his earlier novels). Including several of his best sellers. Forget about anything similar from smaller authors. I'm not aware of any Dutch science fiction authors. I'm sure there are a few. And of course this works both ways of course. It's very rare for Dutch authors to get translated to English. The ones that do have to be successful in the Dutch market first. Which means they need to appeal to a broad audience.
If I were to become a novelist and would try to write some science fiction and do it in Dutch, I'd stand no chance getting any audience. And while I'm comfortable writing in English, I'm not a native speaker and it probably shows. Getting from alright to good is a lot of work and the bar is extremely high.
I have a hunch that AI assisted translations are going to revolutionize the literary world in the next few years. There's a huge opportunity for publishers to broaden their markets for already proven authors to essentially the entire planet. Of course that won't make things any easier for new authors.