Here is what I know about Fedora on Playstation 3:
The last Fedora that was compatible (out of the box) with the petitboot/kboot bootloaders is Fedora 12. That is the distro I use on mine and I use it every day. But I believe all Fedoras going back to FC 5 or so are all compatible. After Fedora 12, the next Fedora with a PPC build is Fedora 16. I've tried that one and it would not boot from petitboot. Some hacking may be able to resolve the problem, but if u want a distro that just works (like I said, out-of-the-box and with no hassle) then Fedora 12 is your distro.
Fedora 12 is old, yes, but it is upgradable (like any Linux) if u don't mind compiling your own software. On my PS3 I've been able to modernize not only the kernel, but also a butt-load of apps that I use constantly (tmux, git, openssl, openbox, fluidsynth, openssh, vim, mplayer, mencoder, ffmpeg, etc... its a long list). Some of the software packages I build for my Fedora 12 PS3 are newer than the ones available for my laptop/desktop (both Fedora 36) from the official repos. My goal that I'm working towards is to package some of these apps as RPMs and make them available to the community from a yum repo on my website http://ps3linux.net. Bookmark that page if Fedora on PS3 is your thing
I would also say that there are tons of advantages to running Fedora on PS3 as opposed to some other distros. For one, there is a crap-ton of software available to install from the online repo archives (all of which are still live - with mirrors around the world), unlike Red Ribbon lol. Also, if (like me) you're interested in learning about the Cell processor and development (High Performance Computing, clustering, etc.) the IBM Cell/B.E. SDK installs and works on Fedora 12 (again, right out of the box - no head aches) and not just the stripped-down PPU/SPU toolchains with libspe2... I'm talking the full suite of supercomputing frameworks that were produced/ported for the Cell (ALF, DACS, LAPACK, etc.) With Fedora 12 on Playstation 3 you will truly never run out of fun new things to learn about or to try.
T2/Gentoo are also options on PS3, but gentoo doen't keep archives of past software solutions for older platforms (as far as I know) so good luck finding the specific source tarballs required to produce a bootable image for petitboot (nothing against Gentoo... its just the way they are). T2 shows a lot of promise if you read the documentation and such, but it won't build on the PS3; you will have to cross-compile from another system (translation: major head aches - very few devs cross-compile if it can be avoided). And from personal experience I have not found a Linux distro yet from which T2 will actually compile. There is something seriously broken about its automated build system and I don't have the patience to fight with it for extended periods of my life that I will not get back. Just trying to learn Cell development is hard enough! Maybe if I had a spare PS3... but I don't. Also, the latest pre-built T2 ISO for ppc6432 (22.5) froze my PS3 when petitboot tried to load the kernel and I had to shut it down by holding the power button till it shut off (I tried this several times). If anyone out there has gotten T2 to build and successfully install on PS3, please contact me and share whatever secret Voodoo you had to use to make it work!
If you'd like to see what Fedora 12 on PS3 looks like, you could check out my Youtube channel: https://www.youtube.com/channel/UCt1mQjAb5WNd9fGsDX-rc9A
Showcasing Fedora on PS3 is pretty much all I do there.
Anyway, hope some people will find this post useful. Have a good day
Disclaimer: You shoud know that on my PS3 I'm using a Sony DEX firmware (3.15) with native support for OtherOS and NOT custom firmware (Rebug, etc). I have no experience with using Fedora on CFW/OtherOS++. It should work the same either way, I don't know why it wouldn't; I've just never personally attempted to install Fedora in that environment... so no guarantees, lol.