Ultimately, I think that art should be accessible to everyone. Piracy is always ethical when it comes to the question of being able to afford something or not.

Otherwise, the way I view the question of ethics for me personally

What do the workers get if I buy it?
Does the studio deserve supporting?
Is the product actually worth buying?

Example: The Sims, developed by Electronic Arts.
EA was voted worst company gods know how many years now. They are part of the forefront when it comes to hiring workers for a project, and then firing as many as possible. The video game industry is a hellhole to work in, and job security isn't a thing at all. If I buy a game from them, I get a license to run it, I have to put up with their DRM, and all the developers, artists, and workers that actually matter have already long since been paid for their work. That's to say, buying it would be unethical because it further feeds the unethical practises of the company, and the money just go to the board anyway.

And that's without Trump and the Saudis entering the picture.

Example: Paralives, developed by Alex Massé and team Paralives Studio. This is a small indie company with a dozen or so developers and artists. They've been crowd-funding the development for years. At this point, if you buy a license to run it you get an early-access incomplete version of the game, missing features, and loads of bugs. I generally do not buy into early access. That said, buying a license to Paralives supports a small indie studio create their passion project. They don't have the same abysmal anti-worker practises as Electronic Arts, and I like their project. At this point they're so successful that me buying the game or not just adds to a stack of money, but they don't have nearly the funds of EA, and I think they're managing them better.

Ethical to buy? I don't know. I'd say it's less ethical to pirate.