I think you underestimate the complexity of figma, greatly. Just one small example is their browser based plugin environment: https://www.figma.com/blog/how-we-built-the-figma-plugin-sys...

Multiply that innovation by a factor of 19,999 and you can see that it’d be hard to clone figma in a way that would pull users from figma to their own product. And while Adobe was copying, Figma would still be innovating.