We are playing God now by artificially and dramatically altering Earth’s set point.
That is still unknown and constantly shifting in predictions.
Yes we should minimize our effects on the environment as much as possible, and we are doing a lot better in that goal, but we still need to live.
I wouldn't say living our lives is playing God.
No, it's not an unknown. Please stop with this cowardly delusion. Human activity is changing the Earth's climate at unbelievable rates compared to the historical norm. XKCD for scale: https://xkcd.com/1732/