Bold plans for Robotaxi, Cybercab, and Optimus haven't been enough to move the needle for the growth stock in 2026.With electric-car maker Tesla (TSLA 3.78%) launching its Robotaxi ride-sharing service in 2025 and with management expecting to begin production of its Optimus humanoid robot this year, it's a great time to buy shares of the growth stock, right? After all, hasn't the stock's 9% year-to-date pullback created a timely buying opportunity?Not necessarily.While Tesla's ambitious plans for the future ...