Unfortunately, most people do not know how to self-filter.
Twitter has always had a List function that makes it a lot easier to only follow tweets from a set list (or many lists) of people. Yeah, you'll still see retweets if they do happen to retweet something you're not in the mood to see. But you're more likely to be able to pick and choose people who won't do that. By self-curating, I rarely see toxic tweets unless I start drilling down into very political threads.
Twitter has always had a List function that makes it a lot easier to only follow tweets from a set list (or many lists) of people. Yeah, you'll still see retweets if they do happen to retweet something you're not in the mood to see. But you're more likely to be able to pick and choose people who won't do that. By self-curating, I rarely see toxic tweets unless I start drilling down into very political threads.