Wicca has no knowledge, it just has style and a muh law of three, and tons of NOISE
Any actual knowledge a Wiccan ever has isn't from Wiccan books but other occult traditions they took information from.
Wicca lacks substance. It lacks real knowledge. Wicca is shit because it's LARP-tier NOISE.
Wiccans just get their knowledge from Hermeticism, from Chaos Magick, from all over the place. The central texts of Wicca will leave you clueless. SOMETIMES a Wiccan does some rituals and by sorcery succeeds and SOMETIMES a self-described Wiccan is guided by god to knowledge. They aren't getting it from the central texts of Wicca though. Wicca has nothing to offer to anyone who wants to actually attain magickal knowledge by way of study.
Does Wicca work? That's not the proper question. Wicca doesn't supply you with any real magickal knowledge, it supplies you with "light candles and wear a witchey dress and chant some words while the moon is full" kind of shit that usually doesn't work for anyone.
Meanwhile other traditions, instead of telling you noise, tell you what you need to know to actually understand magick.
It's like the difference between someone who learns physics vs someone who doesn't know physics but copies some script to use do the physics for them. One could write anything for any physics problem he needs to solve, the other one is limited to just one script for one problem, and begging the more learned actual physicist to write other scripts for him.
Except the scripts Wiccans offer don't even tell you anything at all you need to know to make the shit work for you. It's all a "try it" and if you happen to "have the power" it works for you. They don't know or tell you about the laws magick operates by.