Boots theory doesn’t really apply because it is the exact same phone/hardware. Plus most people don’t really care about reflashing their phone.
As for the privacy stuff I don’t really know much about it in the context of locked phones so I’ll take your word for it.
We do have apprenticeships! For ex: https://www.apprenticeship.gov/apprenticeship-occupations/listings?occupationCode=51-4121.00