It’s been awhile, so I can’t remember exactly how it worked (I’ve used an accountant for the last 30 years or so), but I was able to argue that it went to benefit my day job (which it actually did), and I mixed in a lot of stuff that directly benefited my day job (like taking my team out for a holiday dinner, on my personal expense, as the company didn’t do that kind of thing).
I wouldn’t do it without a decent accountant. In my experience, they always paid for themselves.
I believe that. It's been a very long time, since I declared anything like that. I think I remember my accountant telling me that I couldn't anymore, so I shrugged, and declared what I could. Also, I retired in 2017.
For programmers it wasn't that big of a deal. Maybe some electronics purchases were no longer deductible, or a little bit of software, etc. Home office could be sizeable.
Some other professional got royally screwed - e.g. a concert violinist can no longer deduct a $50,000 violin purchase if they're employed by an orchestra as a W2
I wouldn’t do it without a decent accountant. In my experience, they always paid for themselves.