Though the pictures on the site are just for representation and probably don't represent the date of manufacture on , the batteries you get will most likely not made in 2022.
The “New” descriptor on products doesn't refer to the date of manufacture, rather, it refers to the fact that the product is still factory-sealed and hasn't been used. Many products sit on the shelf for some amount of time before being bought. iFixit makes sure the batteries are still in good condition before sending them out to you.