Most new devices don't have enough space for 5.5x anything. And 2.1mm is the more common one from what I can see.
Regardless it's a crappy choice for consumer electronics because it's got no voltage negotiation. You can fry stuff with it, and chargers aren't universal.
2.1mm is a wonderful connector for switches, sensors, solar panels, and power you need to daisy chain, but PD is pretty much perfect for point to point medium power devices.
USBC seems to break far less often than anything else that's cheap and small. I don't see why 19 pins is an issue unless you just really like simplicity.
It absolutely looks like something that would fail all the time... But it doesn't. Somehow they made it so even the cheap knockoffs are durable.
Inventing a new standard with a weak sheet metal connector and 19 pins to deliver + and - isn't a solution to the above.