This issue has been raised on the forum many times earlier this year ( prior to the May deadline).
But the context was Category Box A or Box D.
Those are the only categories for which the IRS allows an exception to the requirement to detail every sell transaction.
Evidently, there is no way to alter this behavior, which may be new for 2020.
We can't see what is in your data file but if there are many SELLs on different dates, then summarizing for Category Box C is not allowed by the IRS, but the 8949 you posted is valid if there was one sale only.
IRS won't be able to know since there is no 1099-B.
If you want to e-File with TurboTax, you'll have to hope that the IRS will accept the TurboTax behavior (take your word for it) and not make an issue of it.
Given IRS's limited resources, you will probably not have any problems filing this way.
