Yeah so that's a good question. That is how I started down this path, trying to "disprove" what I was researching was somehow pie in the sky aspirations. From what I have found, the vast majority of "it's not going to happen" articles are opinion and looking up the authors they have no real credibility to write what they do. If you find some worth reading, post here, and they can be discussed. There are lots of unknowns in how things will/could be overcome.
As far as avherald and screwing up goes, my point with that is that aviation is not as safe as it's made out to be in the media. Yes fatalities are low but you know as well as I do that the slop in the system keeps us out of the headlines. And automation continues to save our bacon.
There have most definitely been cases where human intervention prevented a mechanical failure from snowballing. They are few and far between. And it's unknown if future automation would have been able to handle those emergencies. But even if it couldn't, the benefits outweigh the risks, similar to how safe cars will become when computers can monitor and make safety decisions.
The secretary of the US Navy said in 2015 the F35 would be the last manned aircraft they bought. Then, a couple years later, they've backed off that as "pilotless doesn't mean unmanned, we still have operators on the ground" as the operating environment on a carrier deck was chaotic. So, maybe the logistics of running pilotless for an airline might be too tough to overcome, at least initially. Maybe there will still need to be someone directly responsible to coordinate all the nuances that happen before, during, and after a flight. And if you're going to have that person there, it would make sense that they have a traditional pilot background.
Soon enough we will take on more of an ATC role regarding aircraft separation. From cruise through landing, we will be assigned an aircraft to follow and make speed adjustments to do so. Approaches will be all RNAV like combining the arrival and approach (similar to how LAX does it now). The computer will make the speed adjustments, not the pilot. AA has scheduled trial runs of this starting next year. If you are interested in seeing what is coming, watch this short video:
https://youtu.be/1-MkAlwDtTg
What you're going to find is the automation is going to be doing a lot more of the flying and decision making.