Sure — for public data that is a reasonable argument. Back when we were having this conversation Facebook had very little data that was shared with public vs the vast majority shared with friends and that is still true today. That was the core of the conversation and what Google folks wanted opened up.
That said — I think they key debate here was about the special sauce of the companies and why they wouldn’t share their special sauce. Google search’s magic is the ranking algorithm. It is why they want it proprietary. Facebook’s magic isn’t the news feed algorithm (they would gladly trade that for google search algorithm to be open!), it is the aggregated data they get from users who want to use Facebook to share it with friends.