What’s the advantage for a NWO for globalists?

No more having to pretend that they're happy with the people having a voice and control. It puts us back to serfs and royalty where the serfs only have what the royalty gives them with no way to fight back.

Are they just evil people?

Evil, greedy, narcissistic, shortsighted, and desperate to maintain power at any cost.

Is NWO synonymous with communism?

No. communism is simply one way to institute new feudalism because that's what it always turns in to. The elites just want a "new world order" with them at the top. communism provides the way to that with them as members of "the party" which controls it but if it didn't we'd see them pushing something else.