We could see a renaissance in that area if technologies similar to Electron and ubiquitous app stores make these more feasible.
(To toot my own horn, I think https://tenet-lang.org/ would be helpful in building well versioned APIs to allow intercommunication with shared semantics.)
In every job I have had, I have begged to get out and talk to users before doing anything else. However, that idea makes folks in charge nervous. It's expensive. It might reveal secrets(?). The users might get annoyed.
One of the biggest issues is that time spent on research is time when the developers can't be developing. That seems to trump everything.
IIRC UX people here on HN has told me Ribbon was a perfect example of UX design done right: they tested it on users and chose the easiest one.
Yet the first version of Ribbon released with the most important menus hidden behind the round logo in the upper left corner.
You are probably a good ux designer, but in general, modern ux designers cannot be trusted ;-)
Only problem there is that as ASICs are developed, general purpose CPU mining rapidly becomes grossly inefficient, so you'd somehow need a decentralized coin optimized for extremely high usage scenarios that was also resistant to ASICs. Not really sure how you'd achieve that latter part without simply constantly changing the algorithm, but it poses a complex challenge of changing the algorithm in a purely decentralized fashion in a way that one can not build adaptive ASICs for. Though I would imagine this is a solvable problem.
For many crypto currencies being resistant to ASIC and even GPU miners is an explicit goal since it promotes decentralisation (everyone has a CPU, few have Asics). The usual way to achieve this is to make memory the bottleneck. ASICs are great for speeding up computation and massively parallelising it, but if the bottleneck is not compute but memory or even better memory bandwidth then an ASIC can't have a big advantage.
Not when you include performance in the "consumer friendliness" side. Existing software is already way too bloated and keeps assuming it's the only thing users run; cryptomining would only exacerbate that effect. Especially that to earn a measurable amount of money over the lifetime of the product, your typical chat app using this model would have to run CPU and GPU at 100% load.
This is really quite a perfect application for cryptoes where everybody could win, but there are a number of not yet solved problems that need to be overcome. One issue with this idea, and as with all good decentralized ideas, is that the person who does ultimately create it would likely receive little reward for it. It's not about making money, but about improving the state of software as a whole. There are only so many Tim Berners-Lees.