I find WoT with no PoW to be entirely deceptive and can be easily gamed by bad actors.
PoW in this context: interacting with nyms long enough to trust them.
So I will politely disagree that it is important.
Discussion
The beauty of GrapeRank is if that's what you want, then you can do that. Every person can have their own ranking and weights. Add PoW to yours.
I'm too simple for that. 🤣🤣🤣
Adding that level of complexity is... Kinda confounding. (Granted, I know zilch about how it works. So I'll shut up now. 🤣)
It's gamable if there is a single algorithm mandated by an authority - a single moving target can be gamed. But when you (eventually) have thousands of overlapping moving targets (different algorithms different settings per user) it makes gaming it futile. So the "best" way to game the system is just to do what you normally do - interact. Over time, you'll grow an organic reputation across all those target.
The number is a proxy, just like colors on animals and plants are proxies for their threat level. Human trust always beats computer trust, but the proxy helps in digital spaces when you want to decide who you care to interact with, or even more important - let into your community.