Exactly. We're adults making fair exchanges for compensation (assuming you've entered into a fair agreement).
There's so many angsty takes in this thread, I'm actually pretty shocked.
Working "hard" is an investment in yourself. You don't always have to be soley running on the SCRUM treadmill - you can learn other things that are valuable to the business. Ideally you'll also be smart and chose wisely for things that set you up better career-wise too.
But the idea that one would treat their employer as some kind of chump that deserves the minimal possible output they can extract from you? That sounds like a great way to pigeonhole yourself into a lacklustre and short career. Not to mention a really unfulfilling life. You spend so much time at work, why not try to find work you enjoy for an employer that isn't crap? I get that many jobs are soulless - but we're still in the drivers seat and we typically have a lot of choices (especially these days).
The premise of a working contract being that you have to work in exchange for a salary...