It's great for what it is! The show runner, Jonathan Kasdan, also wrote for Freaks & Geeks and script-wrote Solo. His goal with Willow was to create a low barrier of entry for people - they don't need to walk into the show knowing all the cadence and customs like one does with shows like GoT or Rings of Power.

Another goal was to capture a very particular 80s fantasy vibe that I think a lot of people on this sub just don't remember. Take Labryinth with David Bowie singing and dancing a song like "Power of the Babe" - it's ridiculous. Or Tom Cruise in Legend, or Ladyhawke, or Krull, or even the later Princess Bride, and then the camp classics like Xena, Hercules, and even Buffy. Even the original Willow is really silly; it has a ton of plot holes, lots of flat characters, plenty of its own bad acting...it's all fine.

Of course it's corny it's meant to be. The show has a ton of heart and that's what I loved about it.