All your itemized deductions (including Donations) have to be more than the standard deduction to get any benefit (so you would only be getting the benefit of the amount that puts you over the standard deduction). And since the Standard Deduction is increased more people will not need to Itemize.
For 2019 the Standard Deduction is
Single 12,200 + 1,650 for 65 and over or blind
HOH 18,350 + 1,650for 65 and over or blind
Joint 24,400+ 1,300 for each 65 and over or blind
Married filing Separate 12,200 + 1,300 for 65 and over or blind
And If you are able to itemize you just get a percentage of your deductions back. Like if you are in the 25% tax bracket for a $100 deduction you will save $25. It isn't added on to your refund. Deductions reduce your income so you get taxed on a lower amount.
