Ever since the election, there has been a large influx of disaffected Twitter users unhappy with Elon Musk's involvement in the Trump administration. I'd be fine with that if not for the fact that they follow back everyone who follows them, including scammers, spammers, and various other bad actors.
The worst example of this is an account called "KamallaDreams," which has over 110k followers and regularly posts racists memes.
This one is ironic considering Kamala Harris' mom is Indian.
Credit to brendelbored.bsky.social for surfacing this.
Now, obvious engagement bait gets enough likes to reach the various trending feeds that don't actively filter them out.
Most microblogging services (not Mastodon) will have some default "For You" page that includes relevant posts from users you don't follow. On Bluesky, the default "Discover" has improved recently, but still needs a lot of work. To be honest, most of my frustration is actually that these new users dominate the reply section under news articles.
My advice would be to subscribe to Engagement Hacks Labeler and Automo, which will label or hide accounts that farm follow-backs. Do be careful, however, when subscribing to moderation lists; most aren't vetted.