Are there any truly FREE AI video tools that generate decent, watermark-free content?

I'm looking to create short explainer videos and social media clips using AI, but my budget is non-existent right now. I've tried a few 'free' tools, only to hit paywalls, massive watermarks, or incredibly restrictive limits that make them unusable. Has anyone found a genuinely free AI video generator that produces decent quality without these common hurdles? I'm eager for any recommendations!