No. HMC is fully buffered and provides a packet-based interface to the CPU it's connected into. This means that the CPU doesn't need to know anything about the memory it uses, and saves die space on the CPU side, but it adds latency. HBM has lower latency than HMC.
Also, GDDR5 does not have higher latency than DDR3. The memory arrays themselves are the same and exactly as fast, and the bus doesn't add any extra latency. GDDR5 doesn't trade latency for bandwidth, it trades density for bandwidth.
Things built to use GDDDR5 often have much higher latencies than things built to use DDR3, but this has nothing to do with the memory and instead about how the memory controllers in GPUs delay accesses to merge ones close to each other to optimize for bandwidth.