I believe rhexs's point is that it's using the same domains for video data and ad data - i.e. you're seeing hxxps://youtube.com/video_data, hxxps://youtube.com/

I believe rhexs's point is that it's using the same domains for video data and ad data - i.e. you're seeing hxxps://youtube.com/video_data, hxxps://youtube.com/ad_data, hxxps://youtube.com/video_data..., so filtering at the DNS level doesn't work.