I’ve been looking at benchmarks trying to ascertain if it is worth it to go with Skylake or Haswell-E 6 or 8 core.
I am surprised to see Skylake 6700k passmark score (11000) is approaching $1000 5690x 8 core i7 (15984).
It seems like beyond latest 4 core architecture their are diminishing returns for higher core counts.
Is this accurate or are 6 and 8 core Haswell-E chips still a worthwhile DAW investment?

Look for DAW specific benchmarks, not Passmark.
Yes, it is worthwhile.