I expected that you wouldn't have many issues given yours where lower density.
I would have expected it to still be difficult based on the frequency scaling for DIMM/rank count combinations that motherboard manufacturers often give (
one example is in this post). You can see that two dual rank DIMMs is often listed as having higher supported frequencies than four single rank DIMMs. Not but much, but it is.
By contrast, here's an example of the scaling on a DDR4 platform. (MSI MAG X570S Tomahawk Max WiFi motherboard.)
You can see that four single rank DIMMs
is slightly easier than two dual rank DIMMs here.
In other words, rank count was a bigger (relative) factor before, but with DDR5 it is now DIMM count that is. Both factors still make things harder to stabilize, but DDR5 is simply many times worse than prior generations just by having four DIMMs instead of two.
The other important difference is that in the AM4 example here, even the worst case scenario gets you the "sweet spot" on AM4. When it comes to DDR5/AM5, four DIMMs almost surely means you will have to drop below 6,000 MHz which is the sweet spot for those CPUs. Probably not a big deal with an X3D CPU in many games, but it's still a drop, and probably a bigger deal on AM5 non-X3D and on all Intel CPUs (which really want even more than 6,000 MHz so this performance drop from four DIMMs is arguably a bigger loss of performance for Intel platforms).
Also, I don't think capacity itself matters a whole lot here (?), but I'm not sure. I tried to read into how much capacity
alone matters and came up with very little information on it. What I found was that it's more about rank count rather than capacity. For example, on DDR5, 4x 32 GB would be harder to stabilize than 4x 16 GB, but (probably?) not because of the capacity itself. It's because the latter would be dual rank DIMMs whereas 16 GB DIMMs are (usually) single rank for DDR5. Once capacity of ICs itself increases to the point where 32 GB DIMMs are able to be single rank (maybe soon since 64 GB DIMMs exist?), then they should be easier to stabilize at higher frequencies than current 32 GB dual rank DIMMs.
