The "best defenseman in the NHL" is all about how you weigh what. Orr could take offensive chances because of his speed in that era. He could typically get back to cover his assignment.
What's "better", though? Someone who has the skill to get back, but has to risk-assess, and may not assess correctly or... The guy who's always in position, always playing defense-first, yet still among the highest-scoring defensemen of all-time?
I personally prefer the latter. Lidstrom, individually, also never got angry or flustered. He had ice in his veins. Possibly the most well-respected defenseman among his peers and officials. In the 3 eras of the NHL he played in - that was simply crazy to me. Even guys like Pavel Datsyuk got emotional, in fights, and made questionable hits.