No amount of preaching will change their minds because they simply think: I'm paying you therefore you should work for all those hours. If you work less , they feel like they are losing money, even though they get the same throughput from you.
I also think part of it about control, they want to keep a close on you, ensure you're don't have time to work on a side project or interview at a competing company .
Being _expected_ to, however, is a different story.
I also think it's crucial to never reply quickly to non-emergencies. Just creates the expectation you're available and encourage more of the same.
That is, unless it's a situation/relationship you want to foster to establish yourself in a team, outpace someone for promotion, etc.
[0] https://medium.com/the-ascent/is-total-work-taking-over-our-...
For whatever reason, employers seem to value this for certain roles, and they often pay a premium for it. This is a Good Thing for people who value money over flexibility; why lock them out of a natural fit? Perhaps you would argue that this isn't good for them, but surely they should be free to make the choice? For those who value flexibility over money, they shouldn't take those jobs. As long as expectations are communicated, there shouldn't be a problem.
Maybe this isn't a real problem, but I want to address it just in case: I'm concerned that some people may feel entitled to a high low-flexibility salary _and_ high flexibility. This sort of entitlement comes up often, and as far as I can tell, it fundamentally ignores economic realities. In other words, if these things are compatible, then proponents need to explain themselves (and provide a lot of support for their arguments) because it's far from obvious.
Developers are not paramedics, our jobs should not require instant availability and the systems should be stable. There is a difference between being productive and being available for random unplanned bullshit.
Even though CVs don't (at least in my country) have DoB you can infer it from years in education. You might not even get a chance for an interview to say "I never want kids, I just want to work hard".
Let's pretend all jobs are like this, where flexibility pays more, if you do ever plan on having kids, could you afford and would you be willing to take a big pay cut so you can spend time with them?
In any case, we can’t function as a society by limiting everyone’s opportunities because someone might be discriminatory. We need to address the discrimination, and we’ve made great strides as a society.
I know a number of people who have done just that - taken a big pay cut - to spend more time with kids. And why shouldn't that be the case? Less work => less pay.
But most tech companies don't need everyone 24/7. They just don't. They should condition employees to value their free time, it will pay off in a lot of ways.
Unless it's an absolute emergency I don't send emails past five. People are conditioned to respond to them. Same with slack messages. There's this belief that being available 24/7 is a positive attribute in employees and we really need to squash that. It's unhealthy for everyone.