You're probably a young'n. This is what everybody thinks until they hit the point in their life where they realize there is more to life than just work (family, friends, hobbies, etc). You'll be complaining soon enough.
In some sense, that isn’t age discrimination by the employer, but you no longer being willing to be exploited.
It would be age discrimination if employers wouldn’t even invite you for an interview, thinking “(s)he’s 50, so (s)he must be wise enough not to fall for the crap story we tell the gullible”.
As long as there are employers where work-life balance is a better match with what you want out of life, I wouldn’t worry about it. And I think there are, certainly in Europe.
