TSLA was down over 6% today. The net effect today on the SPX when TSLA moved down 6% is about 1/10 of 1% or 3.7 pts. Also, TSLA's weighting in the SPX will now be lower than it was this morning so any further moves down will continue to have less net effect. There is nothing to worry about here the system is designed rather well.
Also, AAPL moved up 3.5% today so that accounted for 8.5 points on the upside. And #2 MSFT moved up over 2% for another 4.2 points to the upside. Between the two companies, they offset the TSLA move by 3.5X or 1/3 of 1%.
It's almost impossible for one company to create more than a minor ripple in SPX market valuation, even the huge ones.