Any criticism of MongoDB that does not acknowledge WiredTiger and the plethora of positive changes that made MongoDB much, much better in the 3.0, 3.2 and 3.4 releases is criticism that is not fully thought out.
It's like complaining getting graphic cards working because of drivers is difficult on Ubuntu, based on experience with linux in 2005.
In the end it doesn't really matter. I feel the article is an educational one, but as it's the chance for us to take our sides of the fence in praising and criticising, we'll still do it anyway.
I wouldn't be surprised if half of the commenters haven't used Mongo, or stopped in the 2.0-2.2 days.
A lot of software fails, companies close, while some succeed. Some software that has been hyped up ended up not succeeding, but it doesn't matter. One learns from others' mistakes and keeps growing.
You realize that this sounds like more of the same hype to anyone who was burned by the overpromising in the 1.x and 2.x days? Whether your statement about 3.x is true or not, the MongoDB people dug their own hole that they need to try extra hard to get out of, and so far it's not enough.
It's like complaining getting graphic cards working because of drivers is difficult on Ubuntu, based on experience with linux in 2005.