If Buck isn't at the Skydome then I really can't blame him for thinking that Semien call was a homerun. I give A LOT of leeway to these guys over the past two seasons given the circumstances. My actual complaint about Buck and Pat are when they do their "old men don't like or understand modern baseball" routine.
The Semien one was funny because the camera guy got fooled too, I might tease there but I "blame" Buck less for that if he's not in the park. I was more put off by the Vladdy HR call where he acted like it just scraped by the foul pole when it was probably closer to CF than the line. And that one Tabler joined in on and he is presumably in the stadium so he should've known better.
It's also kind of just a breaking point with Buck/Pat. When you couple those types of repeated errors with their weird anti-stat stances that usually come off more as being out of willful ignorance instead of any sort of rational thought, it all sort of just piles up until all that's noticeable about the duo is how many mistakes they make every game or how often they don't seem to do their jobs as broadcasters.