That’s not actually a solution when talking single-use either. Remaking the bottles from recycled glass is incredibly energy intensive and not an environmentally friendly process either. Multi-use bottles are much better, but the cleaning required also isn’t that simple and also relatively energy intensive (far from remaking the bottles of course).
There’s also practical downsides to glass (heavy, breakable), but those are subjective and their relevance highly depends on the use case.
Ideally, we wouldn’t buy stuff to drink in any kind of bottle, but just use tap water. possibly just buy some concentrated stuff to then make your actual drink at home. Nothing beats the effectiveness of transporting water through a simple pipe, but that isn’t even possible everywhere in the world due to drinking water quality issues…