There are around 100 legal moves for any chess position, and only a handful of rules. The possible actions and rules for building cars is literally all of physics and engineering.
This is a correct upper bound, but the state space is much smaller than that, as the only position that two pieces can share is "captured".
Edit: it's not a correct upper bound (or at least, it may be larger than the state space, but only by coincidence), in that while there are at most 16 pieces, the pawns may be in an officer state rather than a pawn state.
The way I read it was, you have a robot and it:
1. knows it has to build a ferrari (implying it knows what it looks like at least)
2. knows nothing about building, parts, etc
3. can engage in some sort of learning behavior
Once a robot knows it can only connect two parts by screwing them together, it will only try to screw them together, and it might even transfer that behavior over to other parts.
The possible scenarios become much more limited as the robot gets smarter.
Why would learning to screw invalidate other means of connecting things? Why not use an adhesive? Or weld the parts together? Or shape the materials so they can be joined without a separate fastener, like a dovetail or something. Even if it learns those, how does it know there isn't some way of connecting two parts by a chemical means that humans haven't discovered?