Which is one of the prime beefs I have with 5E, actually. If you remove all the game mechanics there seems little point in keeping alignments.
Just as I described - be forced to do something horrible enough while under someone else's control and you'll still have to have an atonement, even though you technically had no choice.It's very unclear how much either short or long term magical compulsion would have on someone's alignment, ignoring effects specifically designed to do so like the helm of opposite alignment.