Sorry, but that’s precisely how reddit works. If someone blocks you - all you see is [unavaliable] when they post.
I barely remember that happening at all in thousands and thousands of hours on reddit. And it's still better than having time wasted typing a comment that disappears.
Reddit is massive. The likelihood of you finding a poster on the frontpage of a subreddit that has blocked you is marginal.
Alright, perhaps I overreacted and piefed deserves to have reddit's head-start growth factored in before judging.