I googled the meaning of culmination and found out it can be used to mean 'climactic point'. Google's explanation is as follows:
the highest or climactic point of something, especially as attained after a long time.
Does this mean, compared to 'climax', 'culmination' indicates that much effort has been put into the process to achieve the climactic point, while 'climax' doesn't? What's the difference between these two words?
Personally, I would use culmination to describe a moment toward the end of something as a result of, as you suggest, effort or struggle.
His degree was the culmination of years of hard study.
A climax on the other hand may also be at the end, but can also be a high point anywhere else chronologically.
The fighting hit a climax on Sunday as protestors took to the streets.
So to me at least there exists a difference in timing and effort undertaken.
