The better question is why is the table real?

Is the reason you think the table is real because it is made of atoms and molecules? Then you would be basing 'reality' on objective idealism: objective knowledge of science.

Is the reason you think the table is real is because Lex and Jordan are having a conversation over it as a place for a podcast? Then you would be basing 'reality' on social idealism: social knowledge of communication and interaction.

Is the reason you think the table is real because if you hit it you will feel pain? Then you would be basing 'reality' on subjective experience: your map of reality is based on what you think and feel subjectively.

Jordan Peterson is mixed up when he makes philosophical arguments, like most scientists. They cannot see beyond objective idealism of science. There are other maps of meaning and 'reality' that are discarded in order to flatten the whole world into objective science.

There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy.