The front page is highly curated. From time to time you will see stories that are many hours old with a handful of upvotes overtake newer and more popular stories.
Those stories are promoted by staff because they are interesting and didn't get the limelight they deserved.
The reverse also happens. For example, many cryptocurrency stories are suppressed because they are neither interesting nor novel.
So in short, yes, votes play a role, but without curation, HN would be a cesspit of self promoting cryptoscams and repetitive content. (After all, how hard could it be to fake HN votes?)
Those stories are promoted by staff because they are interesting and didn't get the limelight they deserved.
The reverse also happens. For example, many cryptocurrency stories are suppressed because they are neither interesting nor novel.
So in short, yes, votes play a role, but without curation, HN would be a cesspit of self promoting cryptoscams and repetitive content. (After all, how hard could it be to fake HN votes?)