Haven't worked 'for' another company in a while, but my recollections jive with the experience of many current colleagues. You're generally expected to be in the office during "working hours", but there isn't a hard "5pm cutoff" time. Someone has an urgent need at 8pm, and you don't answer the call/email/text/whatever, you're dinged as 'not a team player', and will eventually be relegated.

You're often expected to be 'on' 24/7 (as in, not always working, but ready/able to work if need be), but also have to be physically at a location during certain hours. "Vacation" time may be the exception, as long as it doesn't interfere too much with everyone else's work schedules.

I've seen some counterexamples, but they're rare enough in my circles to be the exception vs the rule.