That doesn't seem very redeeming at all. This scene seems to just hammer in the fact that he cares so little about his son that he's willing to brush his death off in a matter of seconds.

Nah it's meant to be a "jerk with a heart of jerk" moment to show that even if he did care about Syura he'd be quick to abandon these feelings.

To the blog poster: Isn't it "Subverting a redeeming quality" right there?

Yeah, literally having to mourn him for just 30 seconds and just quickly get over it as if it is nothing....

You answered your own question. Like to have something be so brief and you go "oh well", one would even question if the grief was even genuine.