Stocks often split when their price is too high and they want to make the share price more accessible to retail investors. Starbucks shares are not high enough to warrant a split for this reason. Stock splits don't change the structure of the holdings since if you own 100 shares at $50, you would then own 200 at $25.

The P/E ratio (as the person above mentioned) would be the same after a split too since it is based on Price per share and earnings per share, you are just dividing by more shares the same number, which will result in the same ratio.

When the selling price is excessively greater than the P/E ratio