On Mastodon, if you follow someone and you want to see their posts but not their boosts, you can hide just their boosts without blocking or muting them. This doesn’t affect their normal posts, and they have no way of knowing you’re doing it.
Log in on your server’s website, and go to the profile of the person whose boosts you want to hide. Click on the ︙ button and select Hide boosts from. If you change your mind, go back to their profile and select Show boosts from.
This only works on accounts you follow.