I was on a team trying to setup a spinout company in Australia of all places. My corporate overlords built a team, boy band style, to go investigate the market with a minimum product, really experienced people who had seen and done a lot. About half the team was on their second career after retiring out of their first, but all were brilliant. I think we added it up and there was something like 170 years of experience in my small group (I was by far the junior person on the team).
During the sit down on the marketing meeting a new person was introduced to the team (not unusual). They came up to the group and was obviously another senior, experienced addition to the group, hopefully with a long and interesting career behind them.
They walked up to the front of the group and introduced themselves, "Hi I'm <name>, I went to Yale" and sat down at the table and proceeded to offer nothing of any substance over the next 8 weeks until they were quietly asked to go "contribute" their Yale credentials somewhere else.
I've been hit with every kind of credential wagging since then, "When I was at McKinsey..."* or "When I went to Harvard..."+ are usually immediate signs of an immensely useless person and I go out of my way to avoid them. It's actually kind of pathetic.
The best people I've ever met actually seemed a bit shy about notable credentials in their past and it wasn't until after months of probing that I could finally learn about some cool job or notable place they went to school.
* I wrote this before reading the article
+ seriously, it's like a cliche