I think is true the org can hint at you the company culture, but an IC to manager ratio of 5:1 is just too many managers IMHO, and without really knowing the manager's responsibilities and quality, the ratio won't tell you much in itself.

I think you were downvoted because the ratio hardly tells you anything conclusive about the qualitative aspects of the org that are more important. Getting to know the org chart definitely helps ask questions that will reveal the culture during the interview though.