How many GB is normal daily use when watching Netflix or Youtube, is 20 GB still normal or a lot?
I would say it is little.
I would say a lot
That depends extremely on which codec and which resolution and bit rate.
A good 4k video stream h.264 with AC3 and bit rate can make up 32MBit / s, then your 20GB would be used up in a good movie (~ 90 minutes). With h.265 you only need roughly half the bandwidth with FullHD a little more than a quarter, with 720p only about an eighth (means a 720p h.265 stream you can gawk with 20GB / day almost without interruption).
Since the answer is a feature film that runs around the clock without a break or sleep, the question can't be answered with the information.
Depending on the resolution / codec / bit rate, 20GB is not that much for films or series.
https://help.netflix.com/...de/node/87 gives Netflix the data consumption at the different resolutions. Ultra-HD / 4k uses up to 7GB per hour. With FullHD it is only up to 3GB per hour.
After about 3 hours of 4k content on Netflix, you would have reached 20GB of data. With FullHD it would be almost 7 hours. A combination of 4K and FullHD is possible.
https://www.androidauthority.com/how-much-data-does-youtube-use-964560/ YouTube was tested with data consumption. At 2160p / 4k / UHD, YouTube uses 5.5GB and 23GB per hour. With FullHD / 1080p it is between 2.5GB and 4.1GB per hour.
With YouTube in 4K, the 20GB can reach between under an hour and approx. 3.5 hours. With FullHD it is between 5 and 8 hours. Here, too, combinations between the resolutions are possible.
