I have 2 android devices, asus and xiaomi. I don't really use much them, meaning the few times I do I have several standing updates, most of them from f-droid.
On debian I enter a command and the machine downloads and executes all standing upgrades at once.
I don't know if I don't understand android, but on the gui I have to first download the application and then click again to install it. I am never shown an option to bulk download and install, which would save much time.
Is it supposed to be like this? Is there something I don't know?
And if you are installing one by one, you do not have a separate download and install step. And you don't have to wait before starting another install.