I joined the forum just to see what solutions people had found; if anywhere is going to have built up a wealth of knowledge and experience about smart TVs for cognitively impaired users, it'll be the AS forum, surely?
It's sad to see that others have had no further joy with this. I've spent quite a while researching accessibility and usability of smart TVs because I want my grandparents to have some stimulation whilst they're sat at home. My grandad has difficulty learning new procedures; anything with more than two or three steps, and as many options, is confusing and ends up frustrating him (he doesn't have dementia or a diagnosis of any kind of impairment, by the way). He wanted to use iPlayer on his temperamental and slow Toshiba TV, but the latency of the TV's interface and the overwhelming complexity of iPlayer's interface has deterred him from using it (I tried to raise the issue with individual members of iPlayer's development team on Twitter, but I didn't get a response). As a consequence of a serious infection and subsequent hospitalisation last year, my nan seems to have acquired MCI (I think. We don't actually know. A GP diagnosed something recently, but we don't know what exactly), which presents as deteriorated working memory, reluctance to speak up about a problem, and having limited ability to follow a simple procedure.
Having our own smart TVs here, I know straight away that they're too complicated and abstract for my grandparents to use comfortably. My efforts to find a viable and affordable solution now showed that usability and inclusion for people with cognitive impairments just doesn't appear to be a factor for manufacturers, developers and campaign groups. There are no reviews, guidelines for best practise, standards, or support resources recognising the issue. There are accessibility features for smart TVs, but these are almost exclusively for hearing and sight impaired users. Perhaps the closest thing I've found to a resource is the GARI website, but it doesn't explicitly account for cognitive impairment in its work; and its product search feature doesn't work anyway.
To be fair, the issue seems to apply as much to other technologies like tablets and mobile phones. Again, manufacturers account for hearing and sight impaired users, but the usability of their products are very similar to ordinary consumer devices. There are a very small number of specialists who have produced usable tablets, phones and/or apps for elderly users, although these are expensive and, with one exception, haven't considered dexterity for the physical form and handling of their products. It's depressingly disappointing.
I had considered designing, prototyping and testing my own solution - based around those cheap Android TV dongles selling for around £30 - with an unambiguous and simple interface, but my resources are threadbare and my technical abilities only take me so far. The conclusion I'd come to about the TV itself was that, actually, it needed to be a 'dumb' TV, with only channels and the basic configuration options available, much like old TVs worked. No menus, options, ambiguous icons, multiple choices or rabbit holes to get lost with. These kinds of TVs don't really retail in the UK anymore, so the only option I could find was to import them from Chinese manufacturers.
As things stand, I think it will be a case of going to Curry's and spending a bit of time 'auditing' a range of TVs there and choosing the most appropriate one. My grandad is keen to use iPlayer - especially during the winter months - so I suppose the fudge will be a case of creating easy-to-follow, printed, visual documentation for him to try with (did you know that there's no printed accessible documentation for iPlayer?).
Anyway, 'hi'! Just though I'd unload my bit of frustration and bewilderment there as my opening contribution to a thread...