I don’t have time to wait >10 minutes every single time I want to test any little change, when there’s no information online and no hints as to how to fix it whatsoever and a shortage of people even using it. Using HTML5.
Even if I didn’t have an incoming deadline with actual development that needs doing this wouldn’t be realistic.
You can do a quick launch onto the platform and test what you’ve been working on.
[Documentation: Launching to Devices][1]
Launching Unreal Engine Projects on Devices | Unreal Engine 5.1 Documentation
I was getting 10+ min build times on a small HTML5 project, while using a 6 core / 12 thread i7 @ 4.3ghz and M.2 NVME (~2x faster write ~4x faster read than a regular ssd).
However this passed and they became 1 minute build times, sometimes only a few seconds. I didn’t do anything to solve it, just down the road they sorted themselves out.
It’s possible that I used something from the engine content and it packaged all of it in there perhaps. It’s sorted now though.
The first package or launch will actually take the longest. Once you’ve gotten that part over with, the packaging process becomes a lot quicker. 
I know, this wasn’t just once, or the first, it was always for a couple days