Ryan Law’s five traits of good thought leadership:

Personal: Everything we share in thought leadership has to, in some way, come from you and be uniquely yours. It has to be a product of the experiences you've had, the lessons you've learned, the problems you've solved, and the people and network you have built up.
Credible: It isn't enough just to share accurate advice; the provenance of that advice also matters as well. If I were to tell you how to win a Grand Prix, even if my advice was technically correct, you wouldn't believe it. Because I'm not a Formula One driver, I'm not even a very good regular driver. So that advice is inherently not credible. Whenever you're writing thought leadership, always keep the question in mind, "Am I credible in this subject matter?"
Persuasive: You are fundamentally arguing for new modes of thought. We typically have to overcome the inertia of established ideas and persuade them that our new ideas are somehow more valid.
Helpful. That is the single most important thing when it comes to any form of content marketing. We have to share things that in some way make other people's lives better, can enrich them and make hard things seem a little bit easier.
Defensible. When we are sharing potentially controversial ideas, we have to be willing to stand behind them and be in for the long haul. It's okay to change our mind based on new information but we can't vacillate wildly between contradictory opinions because that becomes insincere, and that undermines our credibility.