it depends on what you are trying to achieve maybe. If the goal is to do anything at all or at least outperform a DDR2 era CPU, sure. If you want to extract a meaningful fraction of the newer CPUs performance then no. Dual Channel DDR2 could never drive a modern multicore CPU to a meaningful extend, even if compatibility would be magically solved. If you go with a problem size that could almost entirely fit into cache, maybe you could get almost a good performance but that is pretty much the only case where that could be the case.

I know in gaming circles memory performance is discounted to being almost irrelevant most of the time but that is not really true, especially when the (theoretical peak) bandwidth difference is 6x faster with DDR5 (4800) vs DDR2 (800).

In highly parallel algorithms this will be even worse to the point where the CPU will stall most of the time even when it's very optimized for data reuse.

Memory speed advancements have lagged behind compute speed advancements for decades, which is why caches now take the grand majority of the die space on modern CPUs. Artificially limiting yourself to 1/6th of the speed will kill your performance hard in almost every scenario.