Zen 6 is likely to be on AM5 also.
This slide suggests AM5 socket support until 2026. New CPUs will release on an annual cadence, suggesting that Zen 6 will follow in 2025, unless it is delayed.
AM5 is still pretty new, and I doubt they would change the socket without a good reason.
There's no draft specification for DDR6 yet (probably will be drafted in 2024), I don't think DDR6 will be available on consumer desktop PCs until 2026 at the earliest, as companies like Samsung aren't due to begin production until then.
I think both Intel and AMD will wait until DDR6 is ready for mass production, before introducing new platforms.