For virtually all regular users who are currently using the community server, nothing changes because the changes to the license don’t apply to them. Instead, this is about what MongoDB sees as the misuse of the AGPLv3 license. “MongoDB was previously licensed under the GNU AGPLv3, which meant companies who wanted to run MongoDB as a publicly available service had to open source their software or obtain a commercial license from MongoDB,” the company explains. “However, MongoDB’s popularity has led some organizations to test the boundaries of the GNU AGPLv3.”
https://techcrunch.com/2018/10/16/mongodb-switches-up-its-open-source-license/