For those looking for this solution on how to copy .ipas with Big Sur or later, I figured it out - if you drag the .ipa from the Finder window to your phone in the "Locations" section in Finder, it doesn't do anything - but if you drag and drop it over the "General" section within your phone in the "Locations" section, it lets you do it and shows syncing in the progress bar.
ogr0fixer
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