It is not proper to renounce a rightly guided and necessary action. Renouncing any such action due to delusion is widely considered as tāmasa-tyāga.
Krishna has already said that relinquishment of actions (karma-tyaga) is threefold. He continues the thread and explains the subject further. First he discusses the tamasa renunciation.
To renounce actions altogether is impossible, as Nature with its three gunas is holding one and all under the spell of ceaseless activity. As long as we have regular food, and it is digested and absorbed into the system, energy will be built, which has to be utilized in the form of various activities. This is a ceaseless cycle. Hence no physical renunciation of activity is ever possible.
Yet, being deluded, making no attempt to redress the plight through inner unaffectedness, some feel they have the option to physically drop all activity. This is tamasa-tyaga. The deluded fail to understand their inner personality and what happens to it by such wrong moves!