We're still doubting about vector tiles.
It's new, modern and flashy, but is there actually a demand for it from the average user? Do people prefer to see things 'moving' while looking for a location?
Downsides:
- double cpu usage.
- needs GPL (strong fingerprinter).
- slow building-up of the map after every move.
Upsides:
- it's better 'on modern computer systems'. (which would count for raster too)
- It takes less bandwith, true, but in comparison with watching a simple video it's nothing.