VUSA is currently yielding 1.13%. Adding back on the 0.07% fee makes 1.20%. This is net of 15% US withholding tax. So we can work out that the original yield on the US shares held by Vanguard must have been about 1.20/0.85 = 1.41%. (Compare VOO which does not pay withholding tax and yields 1.31% after 0.03% fee). These figures make sense, as a Google search finds that the current yield on the S&P500 is 1.37%.
Suppose you are a UK taxpayer paying 32.5% tax on dividends. Compare £100 invested in
(1) VUSA : tax is 32.5% of 1.13, so you net £0.96.
(2) direct investment: tax is 32.5% of 1.41 (after claiming credit for US withholding tax paid), so you net £1.20.
So net 25% more income by directly investing yourself, rather than through the ETF.
You can do similar calculations if your UK dividend tax rate is 0% (because total dividends are under 2000) or 7.5% for a basic rate tax payer.
One would not try to exactly match VUSA nor to continually rebalance. There is no reason to think that VUSA should outperform on a regular basis a portfolio of about 30-40 directly held US shares that are well-diversified across sectors. To my mind the main advantages of buying VUSA are convenience, and avoidance of regret or excitement, when one of your 30-40 does badly or well, respectively.
Direct share investment would allow you to obtain lesser or greater yield, depending on your preference. Maybe you want higher yield that 1.13% and so prefer to buy ABBV, VZ, IBM, etc.