Mine does this as well. I think it has to do with my midgrade subscription tier. I have noticed that it does not do it on disney+.
Have you tried clearing App Data? This will sign you out (it will be like a clean install) so make sure you know your sign in credentials.
Not a bug, it’s feature. Netflix sends low quality image first so your stream starts instantly while the high quality buffers.
Can you check the resolution Netflix is reporting? I had two Bravias and pressing the display button shows the resolution and the bandwidth being used.
Also; is this happening on all titles on Netflix?
Set data usage to high instead of auto in your netflix account settings (in a browser).
What model is your tv. Philips released a new firmware version recently to combat this happening
Speed is not the only factor in an internet connection. I will place money that if it keeps becoming pixelated like that, you've got some packet loss happening.
You can get the same results on a 1Gb connection if you have enough packet loss.