Steam Flatpak or running steam from Bazzite distrobox container. Which one is better for gaming ?

I think the answer is don’t unless you must. Native seems to work 100x better for me

Well that's a massive difference you're experiencing. For me Native and Steam work the same.

To my knowledge there's less overhead to running graphical applications through flatpak.

Source: a small test I did months ago

There is zero graphics overhead.

No issues running it in Flatpak so far for light gaming.

Flatpak is as good as native. I switched from native to flatpak with no perf differences

Flatpak Steam works for me. Can't say I find any difference from native.

I ran that until I needed to install games on a different disk. Impossible for me on Arch.
- You can do this with the Flatpak version of Steam, but you have to give it access to the disks.
  
  Flatseal is the easiest way to do this.
  
  Open Flatseal
  
  select Steam
  
  scroll down to the "Filesystem" section
  
  click on the + icon on the "Other files" area
  
  either put in the full path, or use something like "/run/media" to give it access to all user-mounted storage devices (this value may vary depending on how the disk is mounted)
  
  Restart Steam (if it was running). You should be able to access additional devices.

From my very non-scientific tests on an AMD 6800U device, running steam via Bazzite + distrobox gave me a 0-2fps boost versus running steam on uBlue Kinoite with Flatpak. Mangohud was slightly easier to manage with Bazzite's distrobox setup. I did not test power consumption between the two for mobile gaming.

It seems to me that you'll have to install the whole Bazzite distro to enjoy its goodies. If we're only talking about running Steam, I'd just go with Flatpak for an easy start.

You can use bazzite in a distrobox container and get it running on any distro. I tried in Debian.

Debian schroot in a distro. Give the user in the schroot access to the snd device. Install Steam in the schroot. There, done. It's even portable.

IDK, try it and find out? I run it native and haven't had any issues, and my main concern running it in a FlatPak would be access to system devices like controllers and whatnot. If I ever run into issues, I'll probably give the FlatPak a shot, but I don't have a good reason to at the moment.

I have ran the flatpak version for a long time without any issues for games from Steam. How ever if you want to "add none Steam games to Steam" that are also flatpaks you need to add more permissions to the sandbox. You might want to do this in certain cases for example you want to utilize Steam Input for a flatpak game/emulator for better controller support.