Not everyone can look back at a 10 year long career in the industry to draw inspiration from. Especially for junior engineers, pointing out alternatives (that feel obvious to you) would be important.
That's bullshit. Even ec.europa.eu (the European Commission's website - I have to login there from time to time) sets session cookies on my browsers. Either you've misunderstood what's asked of you, or your manager has, or someone higher up in your organization. But the "cookie directive" has never prevented anyone from using cookies altogether. You don't even need to ask for consent for a session cookie.