[plorkyeran]

They're two separate bridges built decades apart. They put a bike lane on the new eastern span despite it not being very useful at the moment so that whenever a new western span is built it won't run into the exact same issue (and there's some ideas being thrown around for adding a bike lane to the current bridge, but they're all hideously expensive).

[sneak]

Thank you for providing a least-hypothesis that is even more probable than "ordinary racism/classism". :)