We had free speech before social networks and this wasn’t an issue. The problem is when you encourage all the 5000 lunatics who think the earth is pizza-shaped to congregate and consume each other’s content.
They have allowed anti-vaxxer, conspiracy, misinformation etc communities to thrive and flourish and it's happened without recommendation algorithms. It happened because when people can see other's peoples comments they are able to follow them to discover more people like that.
Twitter absolutely uses an algorithmic feed to show you content you'll engage with more.
On Reddit this is somewhat true, but it's a well-known part of Reddit culture (though this has been changing as they've been kicking out more subs) that each sub has its own set of cultural mores, opinionated mods, and memes. There's lots of drama/hate on subs from other subs but you'll see the same phenomenon on the Fediverse or, for that matter, in a neighborhood gossip group.
It's not like these views go away without algorithmic newsfeeds, it just that algorithmic feeds accelerate their spread.