On AMD it still matters because of the IF to RAM speed ratio. Some ratios can actually hurt your overall performance due to, let's call them, timing shenanigans in the SoC.
The recommended (consensus) ratio for Infinity Fabric (FCLK) to memory clocks (MCLK) and BUS clock (BCLK) is 2:3:3. So, for instance. AMD testing with 6000MT/s is not a coincidence, since this is where their overclocked fabric usually lands on an attainable speed for most chips landing on the 2:3:3 "golden" ratio: 6000MT/s -> 3Ghz MCLK -> 3Ghz BCLK -> 2Ghz FCLK. These speeds, while considered overclocking (they technically ARE), it'll be rare for an AMD CPU to not achieve those 3 clocks. Higher speed RAM, to hit all three in that particular ratio, makes it harder and, like I said, different (dissimilar) ratios can actually worsen your performance.
Plenty of sweaty study has gone through in order to achieve that "truth" about AMD and a similar thing happens with Intel, but they handle their ratios very differently to AMD. They also call them "gears". I'm guessing to keep it simple, but it's the same idea behind: a "gear" defines the ratios at which the clocks in the CPU will work at against the memory clocks. I believe Arrow Lake defines up to "gear 4" this generation with CU-DIMMs, but I have no idea what ratios behind the scenes are used for those.
Now, specifically for the VCache'd siblings: the bigger L3 helps hide the latency aspect, but it doesn't eliminate the overall worse latency in AMD CPUs compared to Intel. Also true for bandwidth, which is something I've hated when they call it "effective bandwidth". Such a stupid thing. Anyway, it matters, but ever so slightly less than non-VCache'd CPUs and with the Intel counterpart. Once the L3 is full, then you're at the mercy of the RAM latency and bandwidth to retrieve whatever you need for the calculations.
Regards.