Originally posted by Death Star:

Ark is unique & well known for its dinosaurs. It has a vast map and tons of dinos. Lots of crafting mechanics as well. So players don't get bored fast. Unfortunately, the PVP servers will always eat newcomers alive. Veteran players are centuries more advance, hence no hope for newcomers to thrive and will only get farmed by the oldest players in that server.

Sons of the Forest is unique & well known for its cannibals and biohazzard-like monsters. It focus on PVE rather than PVP. But seems like the AI needs more fixing.

No Man's Sky is unique & well know for its galactic exploration and survival. You can encounter thousands of new species and minerals everywhere you go. And also tons of places of interests, like ancient ruins, mystical objects, robots, etc.

So how is Valheim compare to those survival games? What are the pros and cons of Valheim compared to them?

I think these comparisons are mostly false equivalencies and there's more than adequate threads, videos, and other resources that you can do better due diligence in learning about whether the game is for you or not.