'Context' is not a 'get-out-of-jail-free' card. Malcolm X's pre-Mecca racism, for example. was far, far less heinous than the racism of the America he lived in due to context - but that does not mean it wasn't bad. Likewise, othering a race with benevolent intent is still, at its core, othering a race of human beings.
And in any case, the point is meant to refute the idea that "you can pick literally any other time". That you can pick another time does not mean that the circumstances which force you to do so are right. Even if you still think it is correct to continue this practice, that "It's only 4 hours" is not a valid argument regarding whether the principle of the thing is moral or not.