It's very useful. It adds value, since during this kind of conversation one can offer useful suggestion or another point of view on an issue that they hadn't addressed before (because they were working on something else, for example).
Different use case: incident handling with tight time constraints. In other words: prod offline and has to be brought up asap, but coordination is needed in touching the various systems. A 2+ people voice call is a godsend because now everything is "in sync" and usually updated in real time with what other people are doing.
Your opinion is not unpopular, is just the product of an HN-like echo chamber. People advocating of async-only communications are a small minority that makes a lot of noise, it's a common situation.