It is insensitive, yes, but firstly there are ways to justify what Shirou did (certainly if you consider him murdering Sakura as anything other than completely inexcuseable, anyway) and secondly Toshi had a reason why he felt he had to do it, so I would certainly not call it "sociopathic". Not that sociopathic is the right word to use here anyway, sociopathy implies that you know your actions will hurt people but couldn't care less, whereas this is a case where he didn't realise what he was doing would hurt her at all.