This is the ideal workflow that I would like to strive towards.
Unfortunately, the product designers don't seem to want to let go of Figma. I understand that this helps them think and organise the layout so perhaps it's not really a problem.
Figma and Sketch are fine and necessary for design tasks. We still need to quickly conceptualize and iterate on design ideas, including creating comps for research purposes.
The missing link, often, is then formalizing the design in some form that both developers and designers can use.
At the job I mentioned in my anecdote, we had a guy who lead our design system team. He had string design experience and was also a front end developer. He acted as the interface between the dec Org and the design team to create and develop a component library that was actually used in production and documented on an internal site.
Devs had real code they could use and design could focus on future products and reducing existing things.
Unfortunately, the product designers don't seem to want to let go of Figma. I understand that this helps them think and organise the layout so perhaps it's not really a problem.