Yes write off rules get complicated fast. People generally agree with the very simple example I’ve given but all you have to do is ask “What if you bought a drill while building the fence?” and you’re gonna trigger a whole host of opinions.
But I think sometimes people only see the complicated examples and think “write offs are a scam got it” so I think it’s important to provide an example where most people would generally agree it’s not. It helps people realize there’s some nuance to the discussion.