Generally a session cookie requires that you send over a unique ID. That's usually it. If you use JWTs, you're sending over the same amount of data if not more,

Generally a session cookie requires that you send over a unique ID. That's usually it. If you use JWTs, you're sending over the same amount of data if not more, but now you have to do things yourself instead of just utilizing features browsers natively have. You could utilize a key system to gain the same advantage as not having to use persistence as one gets using JWTs when implementing session cookies, if you wanted, too.