Hope this is the information you need: https://forums.overclockers.co.uk/showthread.php?t=18728620

There are plenty of other drives that only need the same.
LG BH16NS50, BH16NS55, 2nd gen BH/WH14NS40.

Basically majority of drives for the last 12+ months have supported BDXL, but you need more than just BDXL Blu-ray support to playback 4k Blu Rays.
You need various DRM schemes like AACS Legacy+Online for both hardware and software, which I would assume the consoles can side step anyway.

Many 2015 (Even a few 2013 drives) Fuji drives also only require a Firmware update to support Version 2 format disks and/or AACS 2 as per the whitepaper:
ftp://ftp.seagate.com/sff/INF-8090.PDF

Please go on about your intiment knowledge of the manufacturing cost of the XB1S.

You seem very knowledgable on technology in general. Is there any reason you can see why Sony cannot update the blu ray drive to UHD via firmware update??

They never make their money on hardware, it's always through XBL... 

First off, I don't think a UHD drive adds $50. I'm going to say it's probably closer to $15. If so, then the whole profiteering by deletion of features theory goes right out the window. Rather than debate it (honestly, it doesn't matter to me), I'm more than happy to wait and see the iFixit or iSupply BoM break down when they publish them.

Either Sony was shaving costs down to the bare minimum and shifting that BoM budget into what matters most for games, the performance hardware specs (GPU and other logic board upgrades), or they are simply continuing to push the PS4 as a gaming platform, first and foremost.

I think it could also signal a lack of interest in continuing to push retail optical formats like 4K BD, or at least to the degree that they're not trying to push a new standard as was the case for the PS3 and BD, which helped BD as a format but to the initial detriment of the PS3 as a gaming platform because back in the mid 2000s, BD diodes were a costly commodity, which was reflected in the price of the PS3.

Based upon MS' current XBO marketing campaign, which will become more evident as we roll into the holidays, MS is using UHD as their key bullet point feature to distinguish their hardware's advantage over the PS4.

From a consumer standpoint, do you pay $399 for about 2x (more? someone feel free to chime in because I'm not going to compare 4.2 tFLOPs to whatever the XBO S produces) gaming performance, or do you pay $349 for less than half the processing power and 4K BD playback? That's just hardware we're talking about, services and game catalogs are a separate discussion for the purpose of discussing hardware specs.

I haven't looked into a complete breakdown of the PS4 Slim/Pro drives themselves yet, so I can't really answer that question.

However... When the Xbox One and Playstation 4 first launched, the Blu-Ray 4k standard hadn't been fully ratified.
The Original Xbox One and Playstation 4 could actually output 4k already, thanks to the inclusion of HDMI 1.4. (Although limited to 30hz.)

The issue with those consoles actually came down to the drives themselves, from there everything gets pretty messy.

Second, rather than debate whether MS is subsidizing the MSRP of the XBO S in an attempt to become a loss leader, which will fail, because no one believes MS will sell over 20m more XBO S units than Sony will sell PS4 units over the next year, again, I would simply defer to iFixit, iSupply or any of the other reliable hardware sites that do BoM cost analysis of hardware to take the individual guesswork out of it to see whether MS is losing money on each XBO S sold.

When you say 30hz, does that equate to 30 frames per second? If so then outputting 4K video content(via streaming) on PS4/Xbox One shouldn't be a problem considering movies/film/shows run at 24 frames per second? I know Sony are patching the PS4 to run HDR but I wonder why they dont patch the original PS4 to run 4K video.

Basically, yes.

With that said, nVidia actually managed to do full 4k, 60hz on HDMI 1.4 (Kepler) by using compression (merging of the 4 colour channels in the YCbCr space.)
The downside to that approach is that whilst quality overall is still pretty good for moving images, text quality actually took a fairly chunky hit.

There is no technical reason why the "vanilla" Playstation 4 and Xbox One cannot do 4k video other than the video engines in both consoles chips don't have full decoding support, but the work around for that is done in the GPU's shaders. - But that could becomes messy with the Xbox One's snap feature.

I really don't understand why they do not implement at least 4K streaming on the Slim/OG PS4 if it is capable of running video at 24-30 frames. Rendering games at 4k is not impossible considering the GPU/CPU limitations so the HDMI not supporting 60hz is irrelevant.