Narrations describe people of tawḥīd being brought out of punishment, sometimes through intercession and sometimes through divine mercy. Sunni agreement on the non-eternity of sinful believers is also presented as a central basis.
Entering the Fire does not logically entail remaining there forever. Entry may be for a limited period, so proving entry does not by itself establish perpetual residence.
The opposing argument cites verses with the word everlasting; their subjects and conditions require separate study.