Larian Studios Forums Baldur's Gate III Baldur's Gate III - Story & Character Discussion The insane timeline of the main plot (do I even need to tell you that it's spoilers?)

Based on the wiki and Twi's post, the Mind Flayer thing is probably not a lifespan, but a life expectancy. Mind Flayers may not die of old age, but become more likely to die after hitting a certain age.