Will Tandem cycle Taxi services become more common, or are they too impractical?

[VItraveller]

This is something I’m curious about because there are a few experiments with this in the UK at the moment, the side-by-side tandem scheme is mainly for elderly and disabled people in various parts of London to allow them to access shopping and leisure and other things but you have to be a resident of the boroughs in question, because it’s tied to council funding.
There is something like this in Norfolk as well and I believe Paris experiment with an actual cycle Taxi, where you could book a journey and the cyclist would pick you up and you could choose to pedal or not.
it would be a great way to encourage more people to cycle, and it seems to work well for the disabled and elderly but is it too impractical to expand it further?

 

[JohnMcL7]

Do you have any links to existing schemes? From what you initially described I was thinking like a rickshaw type cycle but I can't find nor have seen a cycle taxi where the passenger also pedals.