Worth noting that this is also an ongoing issue with windows. Only apple has actually solved this, and they do so by owning the whole stack. Each apple product has a specific OS, CPU, and motherboard that were all specifically designed with the end-product user-experience in mind.

But for PCs, the OS, CPU, and motherboard are all designed and built by different companies, each only designed to be generically compatible with the other components. None of them are designed for a specific end-product, so features that require all of the components to play perfectly together for a specific end-user experience (like sleep state) often end up not quite aligning.

None of this helps you, but I think it's worth understanding why the problem exists and why it may just always exist. The best bet is that companies like System76 or Valve solve sleep states for specific linux-based products, and then the rest of us maybe hopefully see some benefit from that.

But IMO this is just a trade-off. It's like a pick 2 situation between Customization, Stability, and Privacy (where a reliabile sleep state is Stability). You can have stability and customization, but you'll probably pay a lot, and the company who sold it will want telemetry data to improve the experience for others. You can have stability and privacy, but the product will be very locked down to a specific use case to ensure a stable experience.