The wording is only secondary to my point, which is that this isn't something to prevent. It's not "a security thing". You said "to mitigate the MiTM attack". It's not an attack and nobody should be trying to "mitigate" it. If an app vendor in trying to evade inspection by the user, they're either being shady or incompetent.

And no, most people at least in the reverse engineering circles I'm in/follow, don't say "MiTM attack" when things are done by the user with consent. I've heard MiTM-ing as a verb, MiTM/SSL/TLS proxying/inspection/interception or even (incorrectly) SSL stripping (and surely some more that I don't remember).