For bus, it still depends on the availability of “low-platform” bus. For “KMB”, it’s a bit better cuz’ almost all buses of KMB got low-platform now. You may also download their app to check the arrival… Read more

you may ask the MTR station staff to prepare a portable and foldable “board” to help you to cross the gap. But sometimes it might take quite a period time to wait for the staff to come, or to make sure the destination station got staff who are available to help

yes the gap could be quite big in some stations

yes… It seems that only those wheelchairs under the limit of 24 inches and manually controlled can board the cabin of the tram with the assistance of staff. https://e-cgo.org.hk/travel/en/trip-detail?id=4