Claiming you don’t need or want a safe space of any kind because “life isn’t safe” is the most obnoxious kind of bravery debate.
Life as an entity/overarching concept isn’t safe, sure, but we’re not talking about safety from random happenstance; we’re talking about things we can control. You could get hit by a car tomorrow, but that doesn’t mean you should take a bath with your toaster. Similarly, the fact that some people out there in the world might be callous and cruel is no reason not to avoid callousness and cruelty when you have the option. On the contrary: it’s a reason to insist on more exacting standards when you have the chance to do so.
Part of the opposition to safe spaces is driven by two things:
1. Attempts to turn entire institutions into “safe spaces” are undertaken by SJ advocates, even when making a space safe for one group means making it unsafe for another group, and this can be used as a means of political control.
2. The opposition knows darn well that they aren’t allowed to have their own spaces, therefore they want to deny every other group their ability to make an exclusive space. Part of the reason for this is that SJ tends to make excuses for why their own policies should not apply to themselves.
Combine these together, and “the world isn’t a safe space” becomes a suitable rhetorical weapon - after all, they aren’t allowed a space so they have nothing to lose by it.