It's useful in any situation where you're trying to make the most efficient use of the power available to you. The classic example is communicating with the other side of the world with minimal power, but it's also useful in any situation where there's a lot of path loss, like when HF propagation conditions to your desired station are terrible or if you're bouncing radio signals off the moon.

There are computer-based digital modes these days that accomplish the same or similar things like FT8 in terms of bandwidth efficiency allowing communication in situations where voice modes would not work. There's still a lot of stations still working in Morse code. If you're chasing DX (long range contacts), it is still very useful.

From a social perspective, using morse code instead of voice modes tends to filter out most of the political and health talk I try to avoid.