What is the State and Local Tax Refund Summary section? Why can't TurboTax just import my data from last year like it does with every other section?

If you filed in TurboTax last year, any state refunds will be brought forward, as they were in previous years.  You will see them in the State and local tax refund summary, but you will still need to answer any remaining questions in that section, so TurboTax can ensure that they are calculated correctly on your return.

The state and local tax refund summary is used to report the taxable amount of your state and local tax refund from the previous year, if any.

Normally, your state tax refund is transferred in from your tax return from the previous year if it is taxable.

Your state refund would only be taxable if you itemized your deductions on your previous year tax return, which most taxpayers don't do under the new tax laws. If you know you did not itemize your deductions in the previous year, then you do not have to bother with the refund summary section in TurboTax.

On your 2018 tax return, see if you have a schedule A, that would be the itemized deduction schedule. If not, then you did not itemize your deductions.