FYI, I don't know Jessica personally, though I think we've met at a con once? I follow her on twitter and such because we're in the same community and I hear good things about her work.
Reportedly, for the tl;dr version, ECTC removed mentions of OrcaCon from their feed because they viewed it as a "3-day political event that also had some gaming," and Chance stated that they/he viewed GeekGirlCon the same way. OrcaCon, fyi, is a new gaming con held in Everett, WA in January that has an inclusive focus; the theme for 2017, according to their website, isn't dragons or robots or superheroes, but rather "Race and Accessibility in Tabletop Games." OrcaCon wants everyone to be welcome to gaming, even those who historically might not have been -- especially those people, frankly. It is emphatically not a party con, or a fandom con. It is a gaming and panel con, where everyone plays a lot of games and talks about those games and talks about what games do and why they're cool (and sometimes why they aren't, and how to fix that). GeekGirlCon, also held in the greater Seattle metro, is about girls and geeky stuff and gaming. It's a female-friendly space, run largely by women for women (and those who identify as or are even just friendly to women and people in general).
A lot of my friends have been commenting on social media today about how their presence in gaming is, according to this, political, and will continue to be so until gaming and society change. I think according to the definition being applied by ECTC, that's true. If existing outside a very small norm runs the risk of rocking the boat, then bringing questions of race, gender, age, orientation, and culture will always be "political." When those questions automatically come with you; when you are "other" in some way, even in the spaces in which we're all just having fun; when you have to have questions about the status quo because it was never designed with you in mind, in a space where design is an inherent part of the experience -- these are the ways in which the "political" is inevitable.
I am political. My presence is gaming should not be political. I have a right to be comfortable in a game-oriented space, and if a few accommodations can ensure that without trespassing on anyone else's experience of gaming, then that should be common sense, not a political statement. I have been a gamer for over twenty years, and worked in this industry for over fifteen. I am not a newcomer; my presence and that of others like me isn't news. My pedigree, such as it is, has helped to pave the way for new people who may or may not resemble me, but who have as much right to be here as anyone else -- and that is truth. If you want to call it political, fine, but ask yourself who's making it that way, because it's not me.