4G if you have a good signal is up to streaming video, but if its a busy area the speeds may fluctuate.
From your VDSL2 speed test you should have no problems streaming HD video as it is, and if you are then something else beyond raw connection speed is the issue.
If problem is that you need more speed in the home consider this...
A connection for all the Ethernet connected devices e.g. main TV and games console
Another connection for use by Wi-Fi devices such as tablets and mobiles
This could be two fibre (VDSL2) services and would be cheaper than 4G.