I maintain that CW is still the most effective mode for DX.
I maintain it matters less than any of us would like.
I've worked many expeditions pre-FT8 and post-FT8, that were SSB only. Where the holiday style op just worked simplex or only "up 5" no matter what the op said over the air.
Strait-up, dreary power-fests where the ability to sneak in with tricks like delayed calls were minimal to nonexistent. You just had to be louder. My CW skills were useless.
Similarly, I know friends who still stick it out on 6m on CW with a small dash of SSB. They don't do horribly. But they
do regularly work about 90 per cent of the grids I do in a given season and a bit less than that for DXCC counts.
There's a lot of DXCC
and grids that simply
never show up on CW on 6m these days. On that band, FT8 has become an "arms race" and it's even hard to get more than one 3 KHz band segment going. There's a couple grids near or in the Big Bend in Texas that have been activated a couple of times lately. They are hard to reach and so hard to get (one is on a tiny patch of land on a cliff above the Rio Grande).
There has been, to my knowledge, no SSB and no CW on any of those activations, even though different players have been involved.
Me, I work the DX where the DX chooses to be.
To some extent, not clear how much as I am still new there, 160m is the same. A lot of stations have compromised (short) verticals and that means limited bandwidth. So, nearly everyone tunes their antenna to the 1840 segment whatever else they do. Maybe they have some sort of switch that swaps various coils in and out or something. Absent that, you're going to see a lot of clustering around 1840 these days.
I work CW on 160 when I can. There are a few guys not on FT8. But the sweet spot of my tuning includes 1840 to 1843.