> Reusable bottles is unlikely to be realistic.

It used to be the norm in the UK for milk.

Agreed. Glass bottles were the absolute norm in Europe up to the late 1980s. A widespread re-use network for glas bottles existed (and still exists, esp. for beer bottles). Add on top a glass recycling system dor single-use and spent glass bottles and recovery rates were very good, albeit expensive in terms of transportation and energy use.

Independent of glass, according to Wikipedia over 75 % of all PET-bottles in the DACH region are also re-used before they are recycled (which can mean burning them). So, yes, it is absolutely realistic to have a system where the majority of bottles are reused.