It may be he streaming service more than the ISP.On YT turn on stats for nerds observe than whenever an ad in playing the connection speed automatically increases to max I get 230 mbps on my 200 mbps net connection but then immediately drops when the actual content starts playing varying from 15 mbps to 120mbps..I am yet to understand the logic being used completely but generally 4K videos get better speeds than he content though this is not universal.
