Yes, a large part of the reason Discourse has resisted stronger user-enactable block is that the need for a member to block another is fundamentally a threat to community cohesion. If the moderators can take action to resolve the tension, that’s a healthier outcome than quiet simmering.
The ‘ignore’ feature was implemented due to a dispute that originated entirely outside the forum, making it painful for Member A to read Member B’s posts.
Also: read-blocking would be even more of a farce on Discourse than on Twitter. Just log out and read the posts that way… or have an accomplice, or alternate account, send the content over. And, if someone is willing to go that far to read posts on a private (login required) forum, the moderators already needed to be involved yesterday.