If you compare how Hex + EB Warlock performs vs Longbow + Poison rogue it's indeed favorable for rogues up to level 4, 5-8 it's warlock, 9-10 rogue, 12 back to warlock (if you get to sneak every round and poison present) and yes it's mostly due to extra cast of EB. I haven't checked how Hand Crossbow work in BG3, but they don't push Hand Crossbow build ahead of extra EB casts at same levels. Be mindful that I didn't factor the Imp Damage for Warlock and it can be quite a significant boost.
Comparing just DPR gives half a picture, but I would expect a lot lower numbers for Warlock to consider class to suck.
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Agree with RP side wholeheartedly.
