It can change in the other direction too, through management/ownership changes. My previous regime taught me a lot about how I should limit the loyalty I show, but the current lot (buy out six years ago) do a much better job of not being arseholes.
Like all aspects of work/life balance, it is a risk/reward balance that you need to monitor and adjust as circumstances develop.
I'm old enough to have heard this about a very large number of companies and it's always wrong in the long term.