Blocking is only one way here as well. If you block a user then their comments and posts will no longer appear for you. If there is a comment by the blocked user in a conversation it shows up as ‘There is no record of this comment’ the same as if it was removed by mod action or if it’s the end of the comment chain you just can’t expand it (At least on Jerboa). Blocked communities don’t show in your feed and won’t show up in a search if you try to manually go to it either.
Your own comments and posts will still show to the blocked user however.
I actually prefer the one-way ban personally, but I’m not a poster generally. I would imagine that the people who are enough of a problem to require the two-way ban would just ban-evade with another account anyway.