I'd say powertop is almost useless today. It was designed in an era when individual devices were loosely-coupled, you could simply identify the power hogs one-by-one and fix them. Today, power management is tightly-coupled with many subtle interactions and dynamic behavior. The most-common failure mode today: something prevents the SoC from entering a deeper sleep mode - you can't fix it with powertop, better to start reverse engineering firmware and Windows drivers... :(

I'd say powertop can be worse than useless today. Its suggestions are too aggressive, it suggests min_power which can cause data corruption, instead of med_power_with_dipm which is the recommended value nowadays.

We also use Dell XPS laptops with Ubuntu. We get about an hour of battery life and no hibernate or suspend.

It's made me consider installing Windows and developing inside VirtualBox.

Check `/sys/power/men_sleep`. For me its default setting was the source of poor battery life during suspend.

If you don’t need a dm, I recommend Windows Subsystem for Linux (WSL). It’s been a joy to use so far. GUI applications can run via X11 server (I recommend VcXsrv).

I actually did this for awhile. It was kinda nice from a distraction point of view, as the VM didnt have my bookmarks or other programs.

Did you check `/sys/power/men_sleep`? it was the source of this problem for me on XPS.