The druid can shapeshift (with both werewolf and bear form factors in the demo). The barbarian is naturally a hardcore fighter, capable of using a greater variety of weapons than other characters.
The demo version highlights three of the final five playable character classes: the barbarian, druid and sorceress, and Blizzard has since also taken the wraps off a fourth and fifth - the rogue and necromancer. This is obviously way out of date but gives a good sense of what is being aimed at in Diablo 4. Looking further back, even in 2019 Blizzard showed a playable demo during Blizzcon so, and you can watch video of a one-hour playthrough that was posted online by Phillip Chu Joy. This includes the welcome confirmation that only cosmetic rewards will be available for purchase in its item shop, ensuring that the best gear is only open to those who've actually earned it in-game. However, it's about time we got a new one - after all, this will only be the fourth mainline Diablo in 26 years, so it's long overdue. Indeed, the last release of the game, Diablo III: Eternal Collection, came out for Nintendo Switch in late 2018. When Diablo 4 hits stores, it will have been years and years since Diablo III first came out, although Blizzard has released downloadable content and updates since. "The first thing you will notice about Diablo 4 is we are going back to the franchise's darker roots," said Blizzard game director, Luis Barriga, during the opening keynote of BlizzCon back in 2019. That's obviously now a couple of years behind us, only in June 2022 did we finally get a proper release window - the game will be coming out in 2023. The playable demo at Blizzcon 2019 was apparently just the "first early step in the journey". We’re not coming out soon, not even Blizzard soon." said Barriga (as reported by Forbes). Indeed, for a long time the only thing it had said was that it won't be coming anytime soon: "A game of this scope takes time. In terms of release date, Blizzard has spent a few years remaining tight-lipped.