Usually it's the peering between google/youtube and the ISP that is the bottleneck, internal ISP network and google CDN are usually fine there's just an unwilli

Usually it's the peering between google/youtube and the ISP that is the bottleneck, internal ISP network and google CDN are usually fine there's just an unwillingness to upgrade the connection between them (usually because parties can't agree on terms, some ISP would like to be paid when peering).