I kinda get it -- we've gone a long way to making the earth uninhabitable, and (most) scifi paints a very rosy picture of the viability of space travel. In the US, getting to the moon was an incredibly big deal. The grass looks greener on the other side, and there is a huge emotional investment in this on the pro-space side. On the anti-space side, it looks like an incredible expenditure of resources, dumping tons of CO2 into the air, and for what? So there's a huge fear about the conditions of the earth; opportunity to fix matters being squandered. There's high emotions on both sides, which makes it both more difficult and more important to maintain discipline in discussions.