I was suggesting that MongoDB's marketing claims initially went unchecked here and generally. It seems a lot of people assumed that others had done the due-diligence for them.

They started using it not knowing that it was not very concurrent, that the default transaction mode allowed data-loss, that it was slow when run in safe-mode, that it was not reliable unless replicated etc. (And these were all design issues, not implementation bugs). A lot of those people were pretty badly burned, particularly in the early days.