They are apparently also logging the Steam ID which is unique for each Steam account. In my eyes the Steam ID is PII as very few people with more than one game on it will change their Steam account.
Although making a one way hash is the right way, having no opt-in is not in the EU. Also, you'd be surprised at what counts as PII in the EU. I know I've been after I read a lawyer's blog on the matter (sadly in my native language).
