I don't think audio was omitted merely because this is an MVP and they didn't have the time or resources for it - it's pretty clearly part of the main concept of the product.
I can think of several reasons why this might be a good idea. For example, audio recording on mobiles can be really bad - maybe that makes regular video recording apps less popular. Audio makes the downloads heavier. Audio makes consuming the content require more focus from the user - it has to mute any music, phone conversation, etc. Audio makes 30s of video seem too short to say anything meaningful - omitting it makes 30s seem like a long time for a "moving photo". Etc.
I can't say if any of these things really make for a good product that people will want to use - it still seems fairly ridiculous to me - but I don't know why everyone's so dismissive of the idea that there's any benefit to omitting audio.
I can think of several reasons why this might be a good idea. For example, audio recording on mobiles can be really bad - maybe that makes regular video recording apps less popular. Audio makes the downloads heavier. Audio makes consuming the content require more focus from the user - it has to mute any music, phone conversation, etc. Audio makes 30s of video seem too short to say anything meaningful - omitting it makes 30s seem like a long time for a "moving photo". Etc.
I can't say if any of these things really make for a good product that people will want to use - it still seems fairly ridiculous to me - but I don't know why everyone's so dismissive of the idea that there's any benefit to omitting audio.