Is there a way to block posts from certain groups?

Yeah I have a number of the US political ones muted.

If you click on the forum or group that you want to mute. Like this post is in the SimilarWorlds forum so if you clicked on SimilarWorlds at the top of this post then right at the very bottom of the panel you'll see a flag with Mute/Report Forum next too it...
Click on that and select Mute Forum that will stop any posts or comments from a forum appearing on your feed.
乂º◡º乂

Yes, thankfully. I have most of the religious groups blocked, so unless someone proselytizes on non-religious topics or starts them in other forums I can avoid the bulk of such discussions.

It's worth examining your Groups lists now and again, as SW seems to put you in extra groups randomly and automatically, without your realising it.

Just ignore them. Its what I do

Pretty sure you can mute them