To be fair, this is extremely common, this isn't something Boeing invented yesterday. The whole series of Cessna business jets are on the same type rating. The

To be fair, this is extremely common, this isn't something Boeing invented yesterday. The whole series of Cessna business jets are on the same type rating. The A330/A340/A350 share a type rating. The 757/767 share a type rating. There are almost certainly more differences between a 757 and a 767 than a 737-800 and a Max. Not that 90 minutes on a tablet constitutes a reasonable level of training though.