Before the pandemic, when I was clean shaven I was sometimes mistaken for a teenager or someone in their early 20s
Most recent example was in 2019 when I had two kinda interns (I wasn't their official supervisor but I was the one who gave them shit to do and who they came to for help) who were juniors in college. So I was a full 10 years older than them. They were assigned to a project spanning a couple divisions at work which obviously included people I didn't directly work with. So the first week when I brought them to a manager in the other group for an overview of the project, he started talking to me like I was one of the interns and thought the intern with a beard was the one who worked there.
When I grow my patchy beard that's an abomination, I get mistaken for a Muslim and have had random arabic phrases said to me before I tell people I don't know what they're saying
Also got carded in Dublin at the Guinness brewery when I was with one of my grad school friends (she was from Ireland) but I was 25 and the drinking age in Ireland is 18 so the age difference wasn't as much.