My herd reaction is that I am distressed to see this kind of thread in a SpaceX discussion.
Why? Investment in Tesla is probably good for SpaceX in the long term.
We’re here to discuss the latest Musk-backed company’s achievement. There’s a huge interest in all things Musk. To the point that everything he does seems widely related - I mean how many people here are rooting for his dream of a Mars colony? So I asked whether it could affect another Musk company. It’s related.
You asked if it could "impact" the stock which is commonly understood as meaning a downward impact. Even setting aside the fact that they are different companies, I don't see how a successful demonstration could do that, no. If anything, if you want to make it about Musk and not the specific companies, it should give people more confidence in Musk since it went exactly as planned.
Impact per google: “2. have a strong effect on someone or something” No indication of direction. Lacking this distinction, the direction is implicit from a successful test to be positive.
I think in a stock market context the word is understood differently, as I said.