Computational will get there one day, but for now bigger sensors still rule. One thing we can be sure of is that there is a better camera coming in a year or two.
Any technology that can be applied to a phone sensor can also be applied to a much larger one. FF makers have a larger body that can hold a bigger computer and a bigger battery. If computational can make an iPhone a FF camera, what could it do for a FF camera with regard to medium or even large format? This matters up until the software gets so good it beats the human eye, and it just isn't there yet. I had a very interesting example using portrait mode on the iPhone X/iOS12 where part of the background was glaringly not blurred in a way that NEVER happens at F2 on FF sensors. Progress will be made.
As for the fate of M43, I would be concerned. Not panicked, but concerned. It remains to be seen if Panasonic is bailing entirely on M43, or if their new FF camera is successful (or even any good). I would expect Panasonic to release a strong camera given their history, but blunders do happen. I would worry about the price, but the partnership with Sigma would indicate that there will be a path to reasonable lenses. If the Panasonic FF is a runaway success, I would not be at all surprised to see them back out of M43.
Does Olympus join the L-Mount alliance? That would be huge. If that happens, I feel pretty sure that M43 is doomed.
I think you need big glass to get access to certain looks. The Panasonic 42.5 F1.2 is heavier than most 85mm FF equivalents. It's a great lens, but if offsets the weight advantage while still not achieving the equivalent F1.8, F1.4, or even F1.2 (Canon) of full frame. At that point, M43 offers fewer advantages over a FF sensor. If you are fine with a kit lens and/or shoot in bright light, smartphones are closing in rapidly. If not, larger sensors are the obvious choice to distinguish yourself from the camera everyone has with them.
I tried M43, and did not like the results I was getting. Were there advantages? Absolutely. They didn't outweigh the drawbacks for my photography . I found myself missing my FF setup so often that I gave up and went back.