I'm going to be honest. NOTE: 70% of 1 star reviews are by people who dont own the game. Also NOTE: if you are lazy and dont wanna read then go to my conclusions Part.
Multiplayer:
Pros: Surprisingly fun, around 60-80% of the maps are good, Tons of content with their 16 multiplayer and 4 gunplay maps, awesome gunplay, ttk is alright ig, Lots of weapons, fun camo grind, gunsmith is good, etc.
Cons:
Destruction; I know some people like it and I appreciate sledgehammer trying to add something new but this destruction is very irritating and annoying as you can get shot halfway across a map through a wooden wall and stuff like that, SBMM: Extremely strict as always, HORRIBLE spawn system, I often die many times from when a enemy spawns right behind me, Attack dogs are broken; also their health is way too high (it takes a little over an entire mag to actually kill 1 dog). Overall Great, Rating: 7/10
CAMPAIGN:
Extremely overwhelming, story is very short (feels like 1-2 hours long) even though it should feel as long as Modern Warfare 2019's 6 hours (which had a great campaign btw) and has a very common storyline of war hero's from different theatres of war to try and stop hitler's successor. the storyline is plain and you won't be amazed at all, the gunplay is excellent and graphics are amazing (you can see this in the Paratrooper and Numa Numa trail missions especially.) The campaign in a more in depth perspective would show that's its decently good with lots of great missions and some bad ones. Overall Decent, Rating: 5.5/10
ZOMBIES:
I dont want to talk about it. Overall the worst zombies ever in COD and waste of time; anyone who plays it other than streamers is retarded, Rating: 1/10 (I was thinking of going into the negatives)
CONCLUSION: Should you buy Vanguard?
Yes, you should. The multiplayer is fun with lots of content and gunplay with a decent campaign that is enough to entertain you even if it isnt a "play it again" campaign.