Yeah, the only odd thing about this is that it happened this late. His harassment of families of massacre victims is a thing that went on for years.
All I can guess is that unless something happened behind the scenes, after Youtube FINALLY took down a few of his videos (and Jones falsified into being a much bigger attack) everyone just decided that he is more trouble than he is worth and there have been cabinet meetings in several corporations where they each look at how others have already banned him and being the last one to do so is not good for PR.