>It would cost them much less than 20B to develop a Figma clone and just offer it as part of their suite, they wouldn't have an issue positioning it in the market.

But they are buying existing market share, existing tech and existing talent. It makes sense on multiple levels. It's always easier to buy something than to build it yourself from the ground up.

For example Zuck could've built Facebook's standalone mobile photo sharing app but Instagram was already much ahead with technology, market share(userbase) and mobile photo sharing brand.