1099-s Buyer's part of real estate tax question

I sold my house in 2020. I have an 1099-s like this:

 

https://www.irs.gov/pub/irs-prior/f1099s--2020.pdf

 

Now there is a value for the "Buyer's part of real estate tax" in Box 6. I understand this refers to the portion of the property tax that the buyer is paying for from the date the house was sold to them.

 

I'm confused by the form instructions for Box 6:

Box 6. Shows certain real estate tax on a residence charged to the buyer at settlement. If you have already paid the real estate tax for the period that includes the sale date, subtract the amount in box 6 from the amount already paid to determine your deductible real estate tax. But if you have already deducted the real estate tax in a prior year, generally report this amount as income on the “Other income” line of Schedule 1 (Form 1040 or 1040-SR). For more information, see Pub. 523, Pub. 525, and Pub. 530.

 

I've always taken the standard deduction and never itemized real estate taxes before on the federal return. I plan to take the standard deduction again this year. So I'm assuming I don't need to report the Box 6 value on the "Other income" line?

 

Also what does it mean exactly by "if you have already deducted the real estate tax in a prior year..."? Wouldn't 2020 property taxes be only deducted on the 2020 tax return, 2019 on the 2019 tax return, 2018 on 2018 ... etc. So how is it possible to have already deducted the real estate tax?

 

Thanks for your help.