Err, no. Witches are generally put down for their slowing capability and early magic damage for a cheap cost. Belinda, who can be mincosted fairly easily is still widely used even by DMM players when they actually need a witch. Furthermore, the claims that Yuyu has better dps is a bit overrated. Her attack speed is in fact not that incredibly much better than standard witches and an AW Belinda comes with her passive that grants her a nice deal of extra attack.
...actually, here, let me put down the numbers for you and anyone in the future that keeps going on about Yuyu's "oh so much better dps." I am guilty of this myself, i admit, but that's because i missread a name once, which was Ryuryu, another witch which gains an attack speed passive.
Dps at max AW level with 21% prince buff:
Yuyu: 647atk x 0.53as = 343 dps
Belinda: 689atk x 0.52as = 358 dps
Attack speed numbers taken from here: http://aigis.gcwiki.info/?%B9%B6%B7%E2%C2%AE%C5%D9
Rest is pure math :P