The only time I've ever seen it be a problem was someone who had a like 20 year employment history on their resume and in that 20 years, they NEVER ONCE stayed

The only time I've ever seen it be a problem was someone who had a like 20 year employment history on their resume and in that 20 years, they NEVER ONCE stayed at a company more than a year. Naturally, their most recent jobs were all contracts and they didn't stick around after the contract expired. They expressed an interest in getting away from contracting, so we didn't really worry about it. Still, it's super obvious when someone has a long history of not sticking around. The OP's specific example doesn't sound bad. Honestly, I think 3 years is a typical tenure at most companies. I have only known a few people (myself included) that stuck around a single company more than 2-3 years.