Is it? I mean, like I would never want to invest the time to actually learning how to decipher it. It doesn't seem worth the effort when there are audio ways to convey the information.
The difference is that the IPA tells you how to use your anatomy to create the right sound. Someone with the right knowledge can look at a word in IPA and know how to construct it to get an accurate reproduction.
You might be able to hear an unfamiliar word and try to reproduce it, but in a lot of cases you will only get, at best, a rough approximation unless you also know how to shape your tongue, where the sounds come from and what the accent is.
English is a very forgiving language, generally speaking, but highly tonal languages (like Vietnamese and Mandarin) won’t let you get away with simple mimicry, at least not without a lot of work to nail the pronunciation.
The IPA is invaluable for studying human language, not just _a_ language. I.e.: For linguists.
For individuals wishing to learn a foreign language, the IPA probably isn't super helpful. Your mind needs to learn to pick up on new sounds if you are going to be able to converse anyway and you should definitely learn your target language's orthography to be a proficient reader/writer.
That said, I enjoy learning languages in addition to studying (comparing, contrasting, etc) and have found the IPA helpful to give me a leg up on that. Therefore, I recommend the IPA for polyglots and linguists.
You might be able to hear an unfamiliar word and try to reproduce it, but in a lot of cases you will only get, at best, a rough approximation unless you also know how to shape your tongue, where the sounds come from and what the accent is.
English is a very forgiving language, generally speaking, but highly tonal languages (like Vietnamese and Mandarin) won’t let you get away with simple mimicry, at least not without a lot of work to nail the pronunciation.