Its not very price competitive now. Its moved into the low end N100 territory with ITX boards and while its smaller and a bit less power its no where near as performant. They will still have some use in smaller applications but 5V x 5A is a chunky cable. I am not convinced this is the way now.
My main uses for them weren't ever desktop but tinkering with simple robotics / telepresence, automation, aprs / mapping, 3d printing (octoprint). Seems like the 5 is overkill for that. I guess there's always the pi zero.
Haven't read the article but is it seriously 5V 5A for the power cable? It seems absurd that they wouldn't put a voltage regulator on board to accept a 12V 2A power supply.
Even still I wonder if they could have added USB-PD capabilities in order to use 9V or 15V to bring the current down. A 5V 5A USB supply is very unique (even the previous 5V 3A was niche) as standard USB supplies that we're all used to typically max out at 2.5A. $12 for the official power supply is a decent price but you're severely limited on options if you don't have the official supply.
Yes, USB-PD requires a handshake confirming that both the charger and device are capable of using it.
I didn't look any further than the article listing the power supply as 5V5A so its good that it supports higher voltages, but really odd that it'd push out 25W at 5V as this is very demanding on the wiring since it has internal resistance which causes the voltage to drop with increasing length. The whole purpose of USB-PD is to up the voltage while reducing current to mitigate losses (and heat and wire thickness) and supply much higher wattage without having to use chunky wiring. This has been an issue with the Pi for quite a while which is why you always hear troubleshooting responses talking about having too small of a power supply. Now they've upped the power requirements while still using a 5V baseline. I did see the article mention that it has a voltage regulator capable of handling 20A of current so maybe it's just poorly worded with regards to the official power supply.