There are certainly more qualified and knowledgeable individuals than me on the forum, but here's my understanding.
1. I believed that qualified dividends would not be taxed. Is this belief correct?
Qualified dividends are taxed at a different rate than income. In 2023, individuals with total income of $44,625 or less pay 0% tax on qualified dividends (
source, section 3.03 Maximum Capital Gains Rate, page 8) Given the income you are reporting here, I believe you are correct that you should not be paying taxes on qualified dividends.
If qualified dividends should not be taxed, it appears that mine were not subtracted from the total dividend amount.
The $4,288 number is the total amount of dividends (including qualified).
2. Am I understanding incorrectly or has there been an error somewhere?
I filled out the form exactly as instructed, using my Vanguard 1099-DIV.
While you should not be paying taxes on QDs (and likely are not), they do still contribute to AGI (line 10) and to taxable income (line 15), which is why they are not subtracted at this point of the 1040. As far as I understand, calculating taxes on QDs is done on the Qualified Dividends and Capital Gains worksheet (see
page 37 of the 1040 instructions), which your program likely filled out.
If you have any doubts about the program, I suggest working through the entire 1040 manually. I've linked the instructions above. You could also fill out only the worksheet and confirm that the tax the program suggests you pay matches what you calculate.