Nobody I know using MacBooks has a particular problem with this. A dongle would be required in most cases to connect to an external display in any case; it's not like Apple are selling more dongles.Agreed.
My wife has a MacBook with a single USB-C port. Having only one port has exactly zero impact on her. The only thing she uses it for is for charging, and very occasionally plugging in a tiny hard drive to look at her iPhoto library which is larger than the computer's built-in SSD.
Everything else in her lifestyle is wireless. And that's where Apple has been going for a long time. She is Apple's target market for a single USB port device.
If you're the kind of person whose lifestyle or workflow necessitates more than one port, you buy a computer with more than one port. Doesn't seem like rocket surgery. I don't understand why OC is so upset.
As for Apple selling more dongles, I don't think that's what's behind it. Apple would probably rather have the shelf space for higher-margin in-house products than use the space for SKUs from another company. I doubt Apple is making bank on USB-C dongles.