I regularly engage in meetings when taking a dump, but only when I'm working from home, and of course flushing only on mute. I don't have a problem with that, the other side has no idea where I am anyway.
Everyone knows you're in a toilet due to the acoustics, but no-one is going to bring it up out of courtesy. Everyone also thinks less of you for it.
Yeah this whole thread is absolutely filled with prudes as far as I'm concerned. Everybody poops, get over it.
Why don't you just excuse yourself for a few minutes like any normal human being would?