AFAIK you can configure Linux to go from suspend to hibernate after some hours. Hibernate puts the contents of the RAM on disk so it doesn't drain the battery anymore. You can keep a laptop for months in hibernation without losing a lot of battery.

https://community.frame.work/t/guide-fedora-36-hibernation-w...

The battery issue is likely because sleep is no longer sleep. Laptops have stopped properly supporting S3 sleep, where the cpu is off but memory is retained. Often what you get these days is S1 sleep where the system can be woken by software and start installing updates.

Older laptops don't have this issue so bttery use is no problem.

My chromeos framework laptop also seems to lose little power when sleeping, but I haven't done a long study. I just upgraded the ram to 64gb, so happy I bought this one. Next step is switching it to dual booting linux and chromeos.