Well, at least one reason for different connectors is the fact that USB-C cannot support more than 100W(20V at 5amps). But I agree that literally every single laptop on the market that's below 100W should just use USB-C for charging.
Not just laptops, but electronics.
Recently I had to replace the crappy default PSU for my Synology NAS. It only uses 18W at peak during Read usage with 2HDD. Why do I need a specific power supply for that?
Most Router only uses 20W. TV Set Top Box / Recorder. Active Speakers. Electronic Shavers Battery Powered Small Drills or Kitchen Wares.
I have to search for that specific charger every time,
On the other side, the Dell 7773 I was eyeing for personal use is a seventeen-incher that runs on a plain 65W.
And FWIW, my laptop charger is 2.25A output. There is plenty of room within a 5A envelope for higher current, faster charging battery tech of the future.
5A in the US gives you 550W, not enough to power a microwave. In most (if not all?) countries in the EU you get 1150W from that same 5A.
Discussion: https://twitter.com/USBCGuy/status/1073833717171335168 https://www.dell.com/community/XPS/Dell-XPS-15-9570-USB-C-ch...