The downstream oxygen sensor on bank 2 is reading too similarly to the upstream sensor, which means the catalytic converter is no longer scrubbing exhaust gases efficiently. The car will still drive, but it will fail an emissions test (in provinces that still test) and the catalyst will keep degrading until it's replaced.
Causes are listed roughly in order of how often they're seen on Canadian independent-shop tickets. Always confirm with a scan-tool freeze-frame and a circuit/sensor check before replacing parts.
