Baggs, I think the concerns arose when a poster suggested that it should be possible for someone to legally choose to die just because they had had enough of life and couldn't see any point in going on. No illness, just had enough of life.
This was the step that, for me, sounded the alarm bells. Easing the deaths of the dying, which is the aim of assisted dying, is a very different matter to sanctioning the death of someone fed up with living
If ending your life for any reason is legalised, it slips imperceptibly into people being expected to take it as the option because they are old, perhaps need carers or are 'full of the problems nobody dies of', to quote a phrase of my grandmother's. Not because they want to, but because it is expected of them.
Some have the strength of character to ignore these hints and tips, but not everyone does. Peer pressure works at any age.