At least personal type conversations, “that sucks” is very very often exactly the right thing to say. Even in work situations it can be a reasonable first response, at least with people not too much further up the org chart than you: “The load balancer latencies have just spiked” “That sucks”. (I’d suggest against using it if CTO comes in yelling about the entire network being cryptolockered though. Unless it’s “That sucks, but I told you so. I quit.”)