The covens exist, and view themselves as the real thing.
I view them as a spiritual system fabricated by eccentric narcissists, using what passed for mysticism in the late 1800s. The material used in the fabrication was fairly similar to the stuff used by the masonic lodges, even if it was put together later.
Funny thing is, is that since that time, an actual religion has evolved, even if the roots are as silly bat ---- crazy as Mormons.
One supreme irony is that the very people that the 'wicca' claim to trace their lineage to, would have burned the 'wicca' or otherwise killed them in fancy and painful ways, for being witches.
A few facts:
====ALL==== cultures that believe in human use of magic to the point that their laws take it seriously into account ALSO believe in human ABUSE of magic. Not all such cultures assume all such magic is abuse, but they ALL believe that such abuse happens.
====ALL==== those cultures had a word to describe abusive user of magic, and that word translates to "witch" (So the ancient 'wicca' believed in the existence evil witches....).
====ALL==== those cultures went out of their way to kill, in special and painful ways, witches. (so the ancient 'wicca' hunted and killed withes....)
====ALL==== history we have, supports this.
Truth told, if magic was real, the above is actually sensible.
As for the reality of magic, prior to modern times, probably the most serious effort to get people to abandon belief in magic, at least of the 'human used kind', was by early Christians.
For example, while Charlemagne would happily slaughter pagans practicing within his lands, like all the educated people of his day, he viewed 'human use of magic' to be silly superstition:
When Charlemagne imposed Christianity upon the people of Saxony in 789, he proclaimed:
If anyone, deceived by the Devil, shall believe, as is customary among pagans, that any man or woman is a night-witch, and eats men, and on that account burn that person to death... he shall be executed.
Similarly, the Lombard code of 643 states:
Let nobody presume to kill a foreign serving maid or female slave as a witch, for it is not possible, nor ought to be believed by Christian minds
The problem for Christianity was that while early Christian doctrine was had core on disbelief of magic, the population DID believe, much as they had believed for 1000s of years, and never gave up that belief. Over the centuries that belief infected the church, for a few centuries, but if anything I credit the Christian church for its resistance to the idea, instead of focusing only on the lapse (and temporary lapse at that) into the ancient beliefs of the general population.
A supreme irony, is that except for magic not actually working, absolutely every other aspect of 'witchery' in the ancient world (Christian and otherwise) was REAL, and provably so. To this day we find thousands of 'curse tablets' and similar remains of ancient 'hostile' magic. (and that's just the stuff that left remains to be found...)