Stable USB power supply

I'm looking for a stable USB power supply (even if it does not have a dedicated mounted solution for a mini rack).

The use case is for powering SBCs and similar devices. Modern Raspberry PIs require a 5V/5A power source. Some chargers can provide this, but chargers have two shortcomings:

1. Usually, only one or two available ports will be able to deliver all 5A of current.
2. When you plug/unplug a single cable, sometimes the other ports lose power because a charger tries to re-balance power delivery (which is very annoying if you need to swap a single RPi and all the others reboot)

Technically, it should be possible, as a single port delivers a max of 25W (5V * 5A). Then 4 ports = 100W, 8 posts = 200W. Chargers with both mentioned power ratings exist, but they implement all the power-balancing, and it's usually expected that a single port should be able to deliver 100W when nothing else is plugged).

The main reason is space optimization, of course, as, of course, anyone has a 4x or 8w AC power strip with a dedicated PSU plugged into each socket.