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How could methane-producing Methanosarcina microbes have contributed to the Permian extinction?

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Line graph showing the number of marine animal families from the Precambrian era to the present, with illustrations of key groups such as trilobites, ammonoids, marine reptiles, and diatoms. The graph highlights major extinction events and a rise to 1,900 living families today. — Permian extinction The diversity of marine animal families since late Precambrian time. The data for the curve comprise only those families that are reliably preserved in the fossil record; the 1,900 value for living families also includes those families rarely preserved as fossils. The several pronounced dips in the curve correspond to major mass-extinction events. The most catastrophic extinction took place at the end of the Permian Period.

Research suggests that a population explosion of the archaea Methanosarcina may have significantly contributed to the Permian extinction by altering the carbon cycle.12

The process is hypothesized to have occurred as follows:

Nutrient Availability: Volcanic activity released substantial amounts of nickel, which served as a limiting nutrient for Methanosarcina, triggering a rapid bloom of the microbes.12
Methane Production: As these microbes flourished, their metabolic processes released massive quantities of methane (CH $_{4}$ ) into the atmosphere.12
Environmental Impact: This sudden surge in atmospheric methane is linked to dramatic warming temperatures and ocean acidification.12

Geologic evidence indicates that the resulting carbon deposition in ocean sediments was far greater than what could be attributed to the Siberian Traps eruptions alone, implicating these microbes as a primary driver of the environmental collapse.12