Not nessecary. My character was 154 with 38 vigor when I started the dlc. Nothing one-shotted me like a lot of people claim, not even the first dungeon boss.
Yes, things hit harder but it's a totally new Elden Ring experience. I have the same feeling as playing through a first playthrough. Everything is new and mysterious, you dont know what an enemy will do or what becomes an enemy when you draw close. Its amazing!