I don’t know what those people do, and if they’re happy, I’m glad for them.According to the fans of apps like LumaFusion it gets pretty close to doing it just as well. It tends to be fans of the Mac (rather than iPad fans) who are most upset with the iPad and want it to work identically when there is no reason to expect a touch-first UI to have the same design considerations as a mouse and keyboard first UI.
Note: I am on record here outlining countless ways iPadOS should be improved, but none of them are by bringing macOS to it.
But I shoot 500 to 1,000 45 megapixel RAW files at a time. I dump them to the computer, sometimes separate them into several folders, then bring them up in a thumbnail browser to cull through them. Once I find a keeper, I adjust its white balance, which takes a while, then its exposure (highlights, shadows, etc.), saturation/colors, then I assign noise reduction filtering, crop it, adjust rotation if needed, do local adjustments if needed, watermark, and output to a chosen directory as a JPEG or as a scaled jpeg. Doesn’t work well on iPad.