2-for-1 split vs. 100% stock dividend?

How are the two actions different? Also, how’s a stock dividend to the benefit to the shareholder? Yes, he gets more shares, but the share price decreases proportionately - where’s the benefit?

Stock split does not impact retained earnings and contributed capital. Stock dividend reduces retained earnings by the value of the stock dividend but contributed capital increases as an offset.

Stock dividend reduces average (not total) cost basis for an investor.