Biggest brand should be contextual. Like biggest brand in game development, CPU, etc etc. On that context, I think biggest game developers are EA as of now. And console wise it has to be sony. I also think mobile based game developer Id say the PUBG developers must be at the top.
Im a fan of the Amiibo gaming cards, ACNH has many collectible cards for in game content, who knows maybe pokemon sword and sheild will allow you to purchase special gaming cards that unlock pokemon not in game. Nintendo is the most advanced tech wise and innovative. Nintendo, my favorite brand in gaming.