I'm not a native English speaker and I'm no sure I understand this part correctly : "..., not better serve the C++ programmers, ...". Does it means that improving c++ is not done to help c++ programmers ?
You're reading the sentence correctly, but I think it was a typo and was probably intended to say:
"We need to improve C++ to sustain the momentum and to better serve the C++ programmers, not out of fear of competition."
The accidental repetition of not is not an unusual mistake, and the original sentence doesn't match the tone of the previous paragraph given that he says "I deem something 'major' or 'minor' based on what it does for users"
