I hate adobe and have been actively trying to switch away from them for a while. I work in game development, though, and for some reason no one has made it as easy to directly modify the alpha channel of a texture. It's something I have to do a lot and is probably the one thing keeping me from using krita or affinity photo.
I might be misunderstanding but that sounds different to a specific alpha channel. Sometimes in game art you'll store extra information in the alpha channel of a texture. Or even pack four different grayscale images into the rgba channels of a single texture. Is it easy to do stuff like that?