Is anyone else see that their federal tax due does not change even after entering deductions/credits, etc. It hasn't changed since entering W2 info? It has always.

[SteamTrain]

Sure..hundreds-of-thousands to millions of people.  

With the new doubled Std Deduction, and the 10,000 limit on deducting state and local taxes, it takes a LOT more potential deductions before the itemized deductions take over

....and the Medical Deductions entered rarely have an effect as nothing there even starts to get added to the itemized deductions total until your out-of-pocket medical expenses exceed 7.5% of your AGI.
______________
AND..if  your "taxable" income is  already a zero... adding gazillion $ $of more itemized deductions wouldn't affect anything.

[xmasbaby0]

Many taxpayers are surprised this year because their itemized deductions are not having the same effect as they did on past tax returns.  The new higher standard deduction and the elimination of certain deductions, as well as the cap on state and local taxes have had a major impact.

Your itemized deductions have to be more than your standard deduction before you will see a change in your tax owed or tax refund.  The deductions you enter do not necessarily count “dollar for dollar;” many of them are subject to meeting  tough thresholds—medical expenses, for example, must meet a threshold that is pretty hard to reach.  The software program uses all the IRS rules that apply to the expenses you enter, and it tells you if you have enough to use your itemized deductions or if using the standard deduction is more advantageous for you.  Under the new tax laws, some deductions have been capped—there is a $10,000 limit to the itemized deductions for state, local, property and sales taxes.

Your standard deduction lowers your taxable income.  It is not a refund 

2018 Standard Deductions:

Single   $12,000  (+ $1600 65 or older)

Married Filing Separately    $12,000  (+ $1300 65 or older)

Married Filing Jointly  $24,000  (+ $1300 each spouse 65 or older)

Head of Household  $18,000  (+ $1600 65 or older

Look at line 8 of your Form 1040 to see your standard or itemized deductions.

https://ttlc.intuit.com/questions/4482873-which-federal-tax-deductions-have-been-suspended-by-tax-re...