There’s really no easy way to offload data off Apple devices unless you pay for third party apps, again contributing revenue to App Store. This is why my primary computing device is and will never be an Apple device.
Not sure what the iCloud point is. I don't use it other than for stuff I want to share between my iPad and my Mac. It's not required and to use it as overspill storage is a stupid idea. And as for my Mac I've got a 512Gb one and it has 268Gb free still. That contains everything I have ever done on a computer from 1984 to date, every photo I have ever taken, every bit of code I've written.
Now the pricing I agree is shit but if it's a really a problem, my usual advice to people is to tidy your shit up, stop hoarding stuff and stop moaning about it.