> every time because nobody on the other side of the conversation, person or AI; can tell whether all my previous options are still valid.

But you can, so as long as the interlocutor tells you what assumptions it made, you can correct it if it doesn't match your current mood.

> So yeah, this argument in favor of conversational interfaces sounds at this point more like ideology than logic.

There's no ideology behind the fact that every people rich enough to afford paying someone to deal with mundane stuff will have someone doing it for them, it's just about convenience. Nobody likes to fight with web UIs for fun, the only reason why it has become mainstream is because it's so much cheaper than having a real person working.

Same for Microsoft Word by the way, many people used to have secretaries typing stuff for them, and it's been a massive regression of social status for the upper middle class to have to type things by themselves, it only happened because it was cheaper (in appearance at least).

Okay I think I finally get your point, and I even agree. The comparison with an executive assistant doesn't help much here, because the CEO interacts with only one person over all those delegatable activities, and the expectations are that person already knows all the defaults. That's what makes it smooth. This doesn't scale when you must deal with a different AI for each interaction. Will we get to a (scary maybe) point where Siri/Alexa/whoever can actually be that personal assistant? Maybe, but we're still far from it. So at least for today, the conversational interface is an extra burden. And tomorrow, we'll see.