What's Andy smoking these days? Apple would counter his merchant silicon argument and who's developing full custom chips these days except Intel and AMD. Most merchant silicon in networking are developed using standard cell ASIC libraries.
He's got his head in the clouds these days. Arista will get absorbed into some other networking company if they keep reselling Intel reference designs. Using merchant silicon is good if you want to get to market quickly but you can't hold your lead relying on suppliers. All your competitors have access to the same silicon.