The picture of the combo toilet-kitchen made me viscerally upset. That must be so unsanitary.
You would be surprised, but toilets tend to be the cleanest places nowadays.
However the one depicted is unsanitary for sure.
The absolute risk from accidental liquid contamination or aerosol intuitively seems unavoidable to me...
Having your own toilet in your own kitchen is probably more sanitary than separating toilet and kitchen, but sharing them among multiple people.
And it's easy for a kitchen without a toilet attached to become disgustingly unsanitary.