Only 5 Stronghold tasks for hard western diary. Before it used to be 10.
You're playing on a 40x normie game mode, so it kind of makes sense why you're at 20m slayer xp before completing 5 stronghold tasks.
If you were on realism, you'd have barely hit level 70 slayer.
Haha, I must be very unlucky then. I am 83 slayer, realism and did 95% of slayer via Konar. Currently at 4/5.