What I love about this film is that it's left ambiguous, so you don't know if the family is actually being cursed or if they're just letting their isolation and religious superstition drive them mad. It can be interpreted either way.
The witch(es) in the woods? Maybe just some ladies who decided to give up the Puritan life and live as hermits in the wild. We don't know for sure if they can actually cast spells, or if they're just high on hallucinogenic herbs or something.
Another thing I love about this film is that the language is preserved as closely as possible to the era it's set in. Which is difficult, because we only have a handful of writing samples to tell us how they spoke. You definitely need subtitles to have some idea of what's going on, especially with Ralph Ineson's gravelly voice.
Robert Eggers did his best to accurately portray an era, rather than modernize it for regular audiences, and that's why this is such a classic work. Every film he's created so far has been incredible.
I just watched his film Nosferatu (2024) recently, and it was spectacular! He took the first ever vampire film from the 1920s and reinvented it as an incredibly realistic and terrifying spectacle to watch. Apparently, it's been a dream of his to recreate that classic film ever since he was a kid, and I think he did a wonderful job with it. I'm excited to see what new films he makes in the years to come.