OTOH, I know someone who is a very slow eater, has rather odd and picky eating choices, and drinks a lot with his food. Turns out he had throat cancer, is missing large chunks, and can taste very little. Finds it very hard to swallow, hence the copious liquid.

And, of course, people who talk non-stop while barely eating or playing with their food could well be anything from self-conscious about a diet to suffering from an eating disorder.

So it is, of course, quite right not to pressure people in such situations, as you never know the reasons why. Of course, some people do just like the sound of their own voices and have very little self-awareness.