He beat the record set last year by Japanese climber Katsusuke Yanagisawa, who scaled the peak at age 71. Sherchan was in good health and was descending from the summit, Chetri said.

Can I replace 'scale' with 'climb' without change of meaning?

You could as the result would be the same - he reached the top. However, "scaled" implies to me that he was able to accomplish this with ease.
Hi New2grammar

I agree with Optilang. The following is the definition of 'scale'.

scale (CLIMB) verb [T]

to climb up a steep surface, such as a wall or the side of a mountain, often using special equipment:

The prisoner scaled the high prison wall and ran off.