Unfortunate maybe but hardly "disgusting". For example, the claim that They’ve even lowercased the “Dad” so that people click on it in a panic is utter rubbish. Words like father, mother, dad, mum etc. are never capitalised (where they are not being used as a name, as in "Dad! Dad!!! Watch this!"), just like uncle, cousin etc. aren't. They aren't proper nouns so there's zero need to.
You are right actually. If you use it to replace a name then it is capitalized but in this use, it shouldn't.