"To share a platform" means to stand or work together with someone else on a common goal, idea, or project. It implies collaborating and combining efforts for a common purpose. Full definition
It was effectively saying that people of conservative religious views are not to be trusted and you shouldn't share a platform with them. (totalpolitics.com)
This is possible by sharing platforms for various models. (motorbeam.com)
Businesses often overlook the impact that social media video sharing platforms can have on their sales and marketing goals. (marketbold.com)