I may be wrong but I think in countries like Switzerland the legal framework requires that the patient retains the physical and cognitive capacity to complete the process of dying independently ie they drink and swallow the drug themselves.
So you might be able to travel but not have the capacity to swallow or lift your arms or lift a glass to your mouth when you get there and it’s that that stops you from travelling.
I once watched a tv documentary (was it the Terry Pratchett one; I’m not sure?) that has haunted me ever since following a very brave British couple on their trip to Dignitas which showed the actual process and the husband, who I think had been diagnosed with MND, had to drink a very bitter concoction of drugs. The process was quite straightforward in his case but at the same time it was utterly harrowing, especially for his wife who was right beside him throughout. She was incredibly brave and dignified too.
Obviously dying from MND I imagine is very harrowing also.
Whereas in France, assisted dying does actually mean assistance under strict criteria, if the patient is physically incapable.
I just find the entire subject upsetting tbh and I can’t entirely make my mind up about what is right. On the one hand I believe that every individual is innately valuable, separate from their capacity to do things. But on the other hand there was incredibly dignity, bravery and pragmatism in that gentleman’s decision.
I definitely think it would be a terrible thing to introduce AD in to the UK at the moment when the NHS is so stretched and the elderly are receiving really poor care in some post codes; the potential dangers are obvious in such circumstances.