Yes, the question should be re-opened (but may need re-wording).
It was put on hold on the grounds that it is 'primarily opinion-based'. Lilienthal's answer to this question gives the best objective criteria I have found for when a question should be considered 'too opinion-based':
This is a tricky one and the one that's most up for interpretation. Variations on "Will this improve my chances?" and "What do X think about Y?" are likely all opinion-based. The main criteria is whether there's a "standard opinion" for a particular culture/industry/area.
For instance "Will coming in late affect my career?" could be seen as being opinion-based as some managers will care and some won't. However, in the US and many European countries being late to work (without flexible hours) will negatively affect your reputation in virtually every company. In other countries that's much less of a problem. When properly defined a question like this can be answerable and useful.
The key point seems to be whether there is a standard opinion that relates to the matter being asked about. In the case of this specific question ('How should I negotiate a contacting rate?'), there seems to be a level of consensus in the answers that indicates there is a standard opinion on this: the contracting rate for a particular job should be some significant multiple (3-4x) of the hourly rate for a full-time employee doing the same job. Therefore, this question does not seem to fit the criteria given in the quote above for 'too opinion-based'.
DarkCygnus, in their answer, suggested that the question might also be interpreted as too broad. I agree that the way it is written, in some places, does give that impression. However, I don't think the underlying question of 'how do I calculate a contracting rate?' is too broad - many good answers have been given that address the question within a length that is appropriately succinct for SE.
Perhaps if I were to edit the question to make it less broad, it might be a candidate for re-opening? The fundamental question of how to calculate a contracting rate for a job seems to be a good question for the site and could potentially help many people in future.