They can already grab your binary by using third party tools or by using the Apple Configurator from what I’m seeing.

TIL: iPhone backups on computers stopped including full ipa’s back in 2017…

They're encrypted using FairPlay, so you need either a jailbroken iPhone or a "jailbroken" (SIP bypass while SIP is enabled) Mac to decrypt them. The former will stop being possible soon enough, the latter will likely remain possible for quite some time.