If someone is in ketoacidosis then one could argue that offloading is appropriate and that a sealed tin can six miles up isn't the best place for them.
I can see where this is going. In ten years time we won't be able to offload anyone as they may be suffering from condition X, Y or Z. Smelly breath can be ketosis, ketoacidosis, halitosis and slurred speech can be anything from a stroke, cognitive impairment etc etc and nobody will be offloaded at all for fear of being branded discriminatory and making the Daily Mail.
In reality removing someone is usually a last resort. It's never just smelly breath. It's never just slurred speech. It's combination of those indicators together with inappropriate behaviour. Whatever the cause of the behaviour then offloading is appropriate whatever has caused said behaviour to manifest itself as again it's not appropriate on a plane and one person should never be allowed to spoil or threaten the other hundreds of lives regardless of how unfortunate you are.