Sure, with no earnings growth and no price increase shareholders would be richer due to the cash returned via dividends.

But that doesn't explain why the price you pay for $X in earnings is higher in one case than in the other. (Retained earnings could explain a minimal part of the increase.)

There is no reason for that $100bn company to be a $110bn company next year if it has returned the $10bn it earned to shareholders and it's still going to earn $10bn.