I wonder if another thing that's been holding larger amounts of RAM back is the lack of error correction. Maybe DDR5 will mitigate that problem, although it's still suboptimal that consumer-targetted CPUs don't support ECC.
For most people, 8 GB has been plenty for 10 years now. For gaming, I'd recommend 16 GB, 32 GB if you play a heavily modded Cities: Skylines.
Not sure if it is a compulsory part of the spec, and irrelevant for most laptops since laptops generally wouldn’t use DDR5, but use low-power DDR instead.