It depends of course on how you published.

When I was authoring software (over two decades ago) and a company acted as publisher they took 85% of gross.

For author/publisher relationships at that time, this was pretty typical (book authors/publishers being the closest analog).

Needless to say there was, in addition to the cost of creating and shipping floppies, advertising that the publisher had to cover.

Apple's 30% cut seemed fair to me when the App Store arrived.

I'm not sure if I would try to ship an iOS app these days though. Not because of Apple's cut but because of the race to the bottom that was unleashed shortly after the App Store gold rush: where now you don't appear to even be able to sell a $0.99 app.