The whole point of this discussion is that MongoDB, Inc could make that claim (as you agree)...and we as users of MongoDB will have to spend money fighting off that claim. You'd have to pretty naive to use software that has these terms.
16 karma · joined October 25, 2018
Let say you are a young startup building a cool SaaS solution. E.g. A data analytics solution. If you make heavy use of MongoDB it is very possible that down the line the good folks at MongoDB come calling since "the value of your SaaS derives primarily from MongoDB..." So at that point you have two options - buy a license from MongoDB or open source your work (which they can conveniently leverage at no cost).
Either way if you are SaaS solution doing anything data related I would not use MongoDB having read this license.