It’s my understanding that by “your truth,” most people in fact mean ‘in your experience’ or ‘what creates the best outcomes for you.’ So when people on talk shows say “express my truth,” they mean ‘express my unique human experience.’
But it is for the reasons you outline in this article that it is such a dangerous turn of phrase. By repurposing truth this way, the original meaning of ‘truth’ is lost, effectively destroying the possiblity of any conversation that attempts to get at THE truth. Objectivity will fall out of use in our cultural day-to-day.
I’m no historian, but if I recall correctly, that way lies madness