His main issue dying so fast it felt like playing on HC basically. And I think he skipped Infinite Warfare. Lol, I forgot all about that one.
Oddly enough he enjoyed WW2 a lot, that's the only Sledgehammer CoD he liked. I personally didn't get a chance to play it.
For me WW2 was perfectly decent. I liked it a lot more than Vanguard. This plays so helter-skelter and manic by comparison.