The details about how Quote Tweets contribute to toxicity, and toxicity to engagement are something the Mastodon crowd needs to read.
Twitter migrants are still stuck in the "engagement at all costs" mindset, and really should read this article and the other articles it links to, and reconsider if embracing toxicity is worth the increase in engagement.
Federated social media is generally ad-free, so there's no monetary incentive to chase engagement for the sake of engagement. It's a capitalist mindset people joining the fediverse need to leave at the door.
People shouldn't be leaving Twitter just to recreate its worst features in a decentralized way. Smaller communities with better adhesion are better communities to be a part of. I don't want to go "viral", I just want to communicate with my peers.