NecroFill will come and explain. We've discussed this person several times. Although we've never agreed.

Well, I'll explain my vision of the process, since you mentioned me...
A sword is quite suitable because vampires are former warriors who have been turned into vampires and can no longer imagine themselves without a sword. And with the acquisition of eternal life, strength, and the reflexes of vampires, they become super swordsmen, practically invincible fencers (much better than any of those Vardancer elves)...
Regarding drinking blood... I think it's clear that no one will lick it off the sword, but! No one has pulled out the vampires' teeth... and besides, I hope everyone has seen Takashi Kitano's films (for example). If you cut a neck (any) artery with a sword, the blood will gush out, and it will not be difficult to lean down and drink it... But it will be inconvenient to use teeth to pierce the armor of knights, griffins, the thick skin of minotaurs, etc. - a rune sword is just the thing for making holes in the enemy's body ;)