Okay so "very" may be a bit too forceful of a word. There are bugs, though they are fairly mild to medium at worst. The most common ones are pathing issues on base, the rare humanoid enemy getting stuck under ground, and some hitbox-related problems that are easily circumvented. The biggest issue which the devs are aware of is multiplayer save game corruption and they've released a guide on backing up saves as a temporary bandaid. In all, this is a rather impressive release and should improve rapidly. MUCH worse games with heavier budgets have been released in the last year alone.