Yes, it’s a design choice, in that you have chosen to design something worse for the sake of feeling industrious.

There is no need to show a consent banner for authentication cookies (these are considered “Strictly necessary cookies... essential for you to browse the website and use its features, such as accessing secure areas of the site”). On the flip side the directive on tracking consent covers any method of tracking, it doesn’t let you go “nyah nyah, I didn’t use a ‘cookie,’ I made my own and called it something else!” so if you think you would need a banner for a cookie, you will need a banner no matter how you do it.