> A lot of their recent product development has been to enable further expansion in organisations - "Dev Mode" for developers (which now looks incredibly quaint against LLMs), […] all are about expanding their TAM out of "pure" design.

I don't think this is correct. In my experience no one buys Figma because of Dev Mode only. Dev Mode just makes it easier/faster to go from an existing design to working code. So it is/was a means to increase Figma's moat, not to get new customers or users. (Devs already needed access to Figma before the introduction of Dev Mode.)