I have had many jobs with no vesting in my employee match. Heck for my company I own, I follow the “default” path from guideline 401k, and my match to my employees vests immediately.
(But yes also had 1-2 jobs that the match had a vesting period)
I've never encountered a vesting schedule for employer contributions myself, but I've always been aware of their existence. I think one company I joined had 12-18 month vesting schedule that they'd just recently gotten rid of.
Also places with real pensions have similar vestment periods for the pensions, leave before then and you typically get your contributions back but certainly not the employer’s. Though those are rare outside government work in the US anymore.
