I didn't say you don't need designers. The designers need to create the design language and help with the component library. It should be unique to your company

I didn't say you don't need designers. The designers need to create the design language and help with the component library. It should be unique to your company, but once it is done once there is no reason to do it again unless you want to change branding or update the design for all your companies applications. However, having the designers code out prototypes is a waste of time IMO. They are not likely going to be proficient enough in a modern framework to ship the prototype like the author was saying they do. Design is a full time job and so is front end and at least at the companies I've worked at designing requires full attention of the designers and FE requires full attention of the FE developers.