Should the Tax exempt amount on the summary for the !099 Int section get deducted from the total tax due?

No, the tax-exempt interest does not get deducted from your tax. It's not included in your income in the first place, so it's already deducted. Tax-exempt interest is shown on Form 1040 line 2a, but it's not added into your income, so you are not paying tax on it.

No, "tax exempt" means that is it not included in income, not subtracted from tax.

Please note that the summary screens in TurboTax are sometimes confusing because they report income items that you entered that are no taxable and they report expenses that you made that turn out not to be deductible. These screens tend to show what you entered, not what is on your return.

The only thing that matters is "does it show up on your return?" That's where it matters.