Complaining to other users accomplishes nothing. I have been doing it for at least a week. They either just agree that it's a problem, or claim that it's OK, nothing to worry about, and even actually compliant if you carefully interpret the IRS instructions, etc.
I have also reported the TurboTax worksheet errors that are actually causing this, and suggest you and others do so as well since that should be harder for them to ignore. That means waiting on the phone for maybe an hour or more to talk to someone who doesn't seem to understand, but says they will ask for it to be checked out anyway.
In any case, I guess that's our best shot, so here is the explanation of the worksheet errors behind this error on Line 4a:
Look at TurboTax sheet "1040 Wks" Line 4, the sub-line labelled "Pensions and Annuities". Right-click on the box there and see that it's data source is Line 25 of the TurboTax worksheet "1099-R Summary". Go to that worksheet and see that Line 25 is labelled "Gross distribution transferred to Form 1040, Line 16a". Obviously that label should be changed from "16a" to "4a", and that is a mistake on a TurboTax worksheet, not an IRS Form. Also note a similar labeling mistake on Line 32d of sheet "1099-R Summary".
But the bigger problem is that when there is an amount on Line 25 of the 1099-R Summary worksheet, the 1040 Wks Line 4 that is supposed to take its entry from there remains blank. Fixing that will also fix this Line 4a problem.
