It doesn't have h.264 hardware decoding though, so ironically 4k HEVC/h.265 will probably play just fine but 1080p h.264 might struggle depending on your cooling solution.
Are you sure they said it'll decode 4k h264 smoothly? I'm seeing them saying 1080p is good, but not 4k.
Here's a quote from the article you linked, emphasis mine:
RPi5 can software decode AV1, H264, VC1, VP9, and more at 1080p with ease. In our testing with YouTube and inputstream.adaptive a surprising amount of 4K media also plays.
Note that it's unclear from this quote what Codec the Youtube stream was using, but remember that Youtube is quite low bitrate even at 4k. The implication here is that 1080p h264 is good and low bitrate 4k stuff might be okay, but it will struggle beyond that. Keep in mind that it's not any worse than RPi 4 in that area, but I don't think it's going to be much better either.
You quoted those two sentences, but skipped the three sentences right before them:
BCM2712 supports HEVC 4K60 hardware decoding. It no longer supports H264 in hardware. This might sound odd but it removes the RPi4’s 1080p restriction on H264 decoding and the 4K H264 test media we have has played.
To my eyes this implies it works fine for 4K h264. The sentences you quote from are sort of a "furthermore, at 1080p it can handle these more complex codecs as well" to my initial reading.
I'm not saying you're wrong, just explaining why I parsed this paragraph a bit differently.
Then again, after learning about the crappy things the Raspberry Pi Foundation has done, I'm probably better off getting a used Lenovo ThinkCentre or HP EliteDesk Mini (which I already have) for a much lower cost. I was just excited about Raspberry Pi's finally being powerful enough to handle 4K, but that may be a stretch, too.
It doesn't have h.264 hardware decoding though, so ironically 4k HEVC/h.265 will probably play just fine but 1080p h.264 might struggle depending on your cooling solution.
The folks at Libreelec say it can software decode 4K h264 smoothly
I wonder if it'll be powerful enough to run a Jellyfin server and actually handle some transcoding now
Are you sure they said it'll decode 4k h264 smoothly? I'm seeing them saying 1080p is good, but not 4k.
Here's a quote from the article you linked, emphasis mine:
Note that it's unclear from this quote what Codec the Youtube stream was using, but remember that Youtube is quite low bitrate even at 4k. The implication here is that 1080p h264 is good and low bitrate 4k stuff might be okay, but it will struggle beyond that. Keep in mind that it's not any worse than RPi 4 in that area, but I don't think it's going to be much better either.
You quoted those two sentences, but skipped the three sentences right before them:
To my eyes this implies it works fine for 4K h264. The sentences you quote from are sort of a "furthermore, at 1080p it can handle these more complex codecs as well" to my initial reading.
I'm not saying you're wrong, just explaining why I parsed this paragraph a bit differently.
That seems to work for my needs. The performance improvements according to this video seems promising: https://yewtu.be/watch?v=9hYfQ7bRgZg
Then again, after learning about the crappy things the Raspberry Pi Foundation has done, I'm probably better off getting a used Lenovo ThinkCentre or HP EliteDesk Mini (which I already have) for a much lower cost. I was just excited about Raspberry Pi's finally being powerful enough to handle 4K, but that may be a stretch, too.