> an event on such a scale could cause sufficient particulate matter to enter the atmosphere that it could create a period of several years of insufficient sunlight reaching the surface of the earth to massively disrupt ecosystems and create a mass extinction event.

So the potential cooling effects of large explosive volcanic eruptions (e.g., events like the 1815 Mount Tambora eruption) are not disputed, but this is not actually relevant for Deccan Traps volcanism or the suggested kill mechanisms related to them. For the Deccan Traps as the cause of the K-Pg extinction, the kill mechanism may have been global warming from pulses of greenhouse gases released by the volcanism (e.g., Tobin et al., 2012) or a combination of this along with ocean acidification and ocean warming (e.g., Keller et al., 2020). I.e., flood basalt eruption and its effects do not equal large caldera eruption and its effects.