Most large American tech companies have something akin to a “junior engineer” position as the lowest level in the full-time ladder, that’s handed out to new college graduates, industry hires with only 1-2 years of experience, and otherwise very rarely. Having a masters degree might let you skip it, having a PhD will always let you skip it. People are generally expected to get promoted out of this introductory position at around the 2-3 year mark you mention.