I’m not sure I agree with that either. (Sorry you’re totally speaking my language here). Truth is truth. Water is wet. Fire burns. Wind blows. There is a physical reality that we can not deny.
We CAN think that truth is subjective and therefore delude ourselves into thinking a whole bunch of nonsense, but only because we are imposing OUR ideas upon something external. This is complicated by the fact that things are also ‘empty’.
Looking at a chair. There IS an object there in physical space. That exists. But ‘chair’ is just an idea, yes that part is subjective. But there is a constant in reality that is objective and does not bend to our will.
I think.