Is Darth Revan really as bad on Defence as people are saying? Or is it something else?

Its too early because:
1. Early people often claim failure when they have inferior stars, gear or mods;
2. Early people often claim success when going against inferior teams or young shards or are in a shard chat where they cant be attacked often; and
3. Early people do good valid testing and mostly try to make objective conclusions.

The problem this early is sorting out 1, 2 and 3. Just needs time, IMHO.