Use case
I don't care about the competitive elements of open collaboration, nor about similar methods of keeping me motivated. I get only irritation from notifications about unread achievements, as well as from the "unread message indicator" itself. I improve the maps to make it more convenient for me to use, and distractions like blinking notifications that do not help me do my work are undesirable for me and, as one of the hundreds of developers of this app says,

personally I am not using (achievements), nor planning to use (achievements), (…) and I would be OK with it being removed".

Proposed Solution
A checkbox in the settings is enough.