It won't be a recording that you could bear listening to. Even more professional setups/bigger conferences often screw up the audio so that the recording is basically binnable.

Can't you just record the audio via whatever computer the mic is attached to?

Syncing video to audio is always a pain, but I wouldn't mind desync to see it.

Yeah but for some reason they don't always do this. Also in case they actually do that part right, they often don't give people who ask questions a mic and don't repeat their questions. Then you don't have any idea what the presenter is talking about.

I agree. A cheap (iPhone) recording is still better than nothing.