User blog comment:Mr. Youtube/Columbia and Rapture/@comment-77.100.138.119-20130401231159

What I think a lot of people missed is that the Rapture part of Infinite is set after the events of Bioshock 1 and 2. This means they're post rapture civil war and post Ryan locking down Rapture.

And in order to lock down Rapture, Ryan sets the bathysphears to only work when piloted by someone with his genetic code. Him and as we later find out, Jack.

Think back again to the endgame of Infinite, when Elizabeth takes Booker into the bathysphere, he manages to activate it.

Ponder on that, Internet.