The possibility of a tipping point cascade is generally without dispute as far as I know. It is likely based on what we do understand, however predicting how likely exactly, the severity of consequences, and the interaction with positive and negative feedback loops from other climate systems is not well understood.

The consensus seems to be that it's virtually certain with a warming of 4-5 °C compared to pre-industrial levels.

Ignoring an existential risk like that because one lacks understanding doesn't seem wise.