> All the while where some really smart interns or junior engineers come out of prestigious institutions (Oxford, Cambridge, MIT, Stanford, Harvard, etc), with a stunning body of work and can absolutely run rings around engineers that are called 'senior' in title only and don't have a body of work to show when they leave.
I've hired interns and juniors at my past three positions, from various educational backgrounds including ivy leagues and ivy-adjacent schools (UCLA, CMU, for instance) over the course of the last ~5 years, and I'll give an opposing anecdote.
A lot of people who attend elite institutions are able to do so because they've been groomed from a very young age to have a given trajectory in life. Their entire existence and sense of self-worth seem to be predicted by "prestige" and being better than someone else.
This typically translates into someone who is very difficult to work with, especially when it comes to interns.
The "I'm clearly better than you because I attend $school" attitude, typically coupled with real-world industry naiveté leads to a real "I'm gonna change the world because I'm so special" Spongebob-esque archetype of person. Insufferable to work with, impossible to manage, always off spinning their wheels on something not at all aligned to what the business really needs. Ignore direction, ignore technical architecture, because they assume they know better.
I've also found that they don't really care all that much about their internships, because in their mind's eye, they're the "main character" and they're surely going to move on to something great because they'll be a $school alumnus.
They also tend to not be particularly well-rounded individuals. No hobbies, varying degrees of social ineptitude, anti-social competitive behaviors due to where they attend school.
I really could not care less about a "body of work", I care that you have some aptitude, passion, and are bearable to be around for >= 40 hours/week.
I get your point about senior engineers, a lot of people tend to mentally clock out and settle into their ways, no longer wanting to go above and beyond, typically because they have families, friends, hobbies, and no longer want to participate in a game where there are no winners.
But a clocked-out senior engineer who does the bare minimum, but understands how the business works will still be an order of magnitude more valuable than some $school intern.
> Of course, everyone is different, but I don't get the obsession with not giving very bright and talented juniors a chance even though they are more likely to be cheaper than seniors.
Unless you're working at some cutting-edge startup, businesses don't value merit, really, they care that you understand process, business needs, and the quickest path to execution to ensure continuous revenue.
Interns can be great, or horrendous, and I've personally found there to be an inverse correlation to how good the school they attended is to how useful they actually are in real industry terms. It's simply a trial period for both parties with the ideal outcome being they become a full-time hire once they finish their degree.
When money is tight, as it is now, there's simply no point in taking on individuals who will effectively be a burden for potentially months before delivering any real value.
Regarding your bus factor comment, businesses hedge that senior+ engineers will not be willing to shoulder the risk of job hopping in a shoddy economy, so there's really no concern from that angle of needing to "backfill" with junior engineers who will grow.
This will all get better when money begins flowing more freely again. Just a function of time.