I understand that CPO reliability concerns are specifically with the laser drivers. It's very expensive to replace your whole chip when one fails. Even if the cables are a concern (I've no idea), having more reliable drivers would still be preferable to less reliable cables, given how much cheaper/easier replacing cables would be (up to a point, of course).
LDO is just integration. It certainly has value: integration almost always does. So it's clearly the obvious optimization of conventional serial optical communication.
This new TSMC work with parallel incoherent optics is altogether distinct. No DSP. No SerDes. Apples and oranges.
Ok, but I'm just after solutions to problems I have talking to other chips. I don't mind what's novel and what's optimisation. Whatever is adopted, in either case it's a step-change from the past 20 years of essentially just copper and regular serdes in this space.
And I'm not sure how much of this is actually TSMC's work, the title is misleading.
Edit: actually, they are working on the detector side.