I know there has been much discussion regarding the middle row seat design, and the inability to fold the middle row seats flat. After looking at the design studio, and have a car with similar designed seats, here is an opinion/observation that many may not have thought of.
In looking at the design studio, it looks like the seat belts are part of the seat itself. This design is complex, complicated, and adds demands that non-seat incorporated seat belts do not have. I currently own another vehicle which has the seat belts incorporated into the design, and am familiar with all the demands and requirements such a design requires. To have the seat belt incorporated into the seat as opposed to the body structure (as most cars have) it requires the seat frame and back to be extremely strong. In my current car with incorporated seat belts (BMW 8 Series), the seats do articulate, but do not come close to folding flat. The seat belt frames are reinforced to take extra stress of the incorporated seat belt and are heavy. By incorporating the seat belt into the seat frame, one does not have to "get around the seatbelt" attached to the body structure to get into the row behind the seats. This looks like it would have been a big design requirement by TESLA to make it easy to get into the third row - as TESLA has made a big deal of. Elon has made ease of entry/egress from the back row a major point in his presentations.
To get a seat with an incorporated seat belt to safely secure passengers in place and pass crash tests is probably a big reason the second row seats do not fold flat, but rather tilt forward. By making the seat frame rigid, it eliminates this issue.
This may not be the reason the current seats do not fold flat, but it sure does make sense if you look at it in this context.
In looking at the design studio, it looks like the seat belts are part of the seat itself. This design is complex, complicated, and adds demands that non-seat incorporated seat belts do not have. I currently own another vehicle which has the seat belts incorporated into the design, and am familiar with all the demands and requirements such a design requires. To have the seat belt incorporated into the seat as opposed to the body structure (as most cars have) it requires the seat frame and back to be extremely strong. In my current car with incorporated seat belts (BMW 8 Series), the seats do articulate, but do not come close to folding flat. The seat belt frames are reinforced to take extra stress of the incorporated seat belt and are heavy. By incorporating the seat belt into the seat frame, one does not have to "get around the seatbelt" attached to the body structure to get into the row behind the seats. This looks like it would have been a big design requirement by TESLA to make it easy to get into the third row - as TESLA has made a big deal of. Elon has made ease of entry/egress from the back row a major point in his presentations.
To get a seat with an incorporated seat belt to safely secure passengers in place and pass crash tests is probably a big reason the second row seats do not fold flat, but rather tilt forward. By making the seat frame rigid, it eliminates this issue.
This may not be the reason the current seats do not fold flat, but it sure does make sense if you look at it in this context.