They are making a slight comeback but as more of a leisure thing I think - somewhere nice/novel to go for a stroll on a sunny day, rather than when doing your morning power-walk from the tube/bus station to your office etc (e.g. New York high line type thing)
Universally hated. People didn't want to only go where the walkways let them go. Turns out we're lazy (https://www.theguardian.com/cities/2018/oct/02/walkways-in-t...).
They are making a slight comeback but as more of a leisure thing I think - somewhere nice/novel to go for a stroll on a sunny day, rather than when doing your morning power-walk from the tube/bus station to your office etc (e.g. New York high line type thing)