For me, it very much depends on what the conversation is and who I am talking to.
I'm still able to teach twice a week at my martial arts club - yes, I realise that this sounds incredibly strenuous for someone with ME but I, regrettably, don't actually take part in any of the practice, I just talk, and even then I try to maximise my students practice time by keeping my talking to a minimum. Now, because I know my subject matter, I am in almost total control of the content and I have a small attentive audience then I am able to cope with each 90 min class, but put me in a situation where I had to be part of normal conversation with a similar number of people then I most likely wouldn't last 10 mins. Face to face with just one other person I might do better but it would depend on the other person, subject matter etc.
And taking two examples from the poll, talking on the phone I now find hard, mainly an inability to absorb what the other person is saying, most of the time, which is ironic as most of my career was in telesales, and I listen to music almost all of the time, it seems to help more than it might hinder.
So, I've not voted because it depends for me.