Warlock... i just cant.

Hello there. I recently main my warlock (allready ~6k gs) But never, never ever got even in top 10 of dps as destro. Now im trying to respec my char to Affi but still on ICC25/RS25 i got like ~9k dps with full buff :V On training dummy i reach like 4.8-5.1k dps... what im doing wrong? Full ench and gems for SP+crits + tailo. Shadowbolt with DrainLife procs too rarely, got some hc gear for haste/crit but still nothing... on RHC i saw som ppl with 5.5k gs eq doing better dmg than me...

Trying diffrent playstyles and combination of skills to start but even lifetap dont boost my dmg noticable.

Whatsoever, Black Magic enchant, i think it does... nothing? Proc's poorly, 1 time for... 3 min of dps? Cloak do same thing.

I played a lot as warlock on retail and old classic wow as destro and never had this kind of problem. I know that WOTLK isnt good for casters but fr, shadow priest can do much moar with same gear.

https://armory.warmane.com/character/Lokomotywa/Icecrown/summary