Clinton and her team did as much as they could. I do not know what else she could have done more or differently. Sometimes you win and sometimes you lose.
I personally do not buy the "economic insecurity of white working class" argument. Clinton has repeatedly said that the top 1% should pay their fair share so that the middle class can get a chance to get ahead. She also wanted the U.S. to be a "Clean Energy Superpower" and she staked out her position to build infrastructure for it, which requires labor (e.g. jobs). She was quite clear about it.
Americans instead chose fossil fuel and tax cuts for the 1%. Sometimes you cannot help.
If you don't believe it, then you should look at her "lock" states that she lost to Trump. The states that haven't gone republican since, at least, 1980. Those are the working class voters that you think she was talking to and, county by county, they responded very favorably to Bernie and, after Hillary decided to ignore them through the general, they responded heavily to Trump.
The difference in these 3 states, that were "guaranteed" for her, was something like 30k votes, I think, (only ~1k in MI alone).
Part of the problem is believing that those voters couldn't possibly have mattered. The other part is thinking that the oft-repeated dem message of "making the 1% pay" still resonates. I do believe that still sells, but this looked like an election about personality. She's out there giving substantive policy messages with details and real solutions, Trump is running around saying "Life bad. Jobs good. Me make jobs and make bad people pay!" All the while, The only message and ads the party put out against Trump were about pussy grabbing and such. Yes, she spent tons of time talking about the vacuousness, incompetence, in inexperience, fantasy of his policies, but those weren't in the ads--the things people see.
Trump killed it with getting his vile self on TV and steering the media towards talking about what a terrible human he was, rather than talk about how terrible his policy proposals were.
That is freaking important.
You and I and others spent plenty of time on these pages doing the same: The repubs go after bill Clinton talking about how horrible he was blah blah, but when you point out Trump, it just doesn't matter. Why? Because they don't care. We already elect horrible people to office every year, in every single position. I think the American public has pretty much accepted that as the status quo. So, the more we talk about these things, the less we talk about
what a terrible president he would be. Again, not that people weren't talking about these things, but it was largely drowned out by Pussy Grabbing and making fun of disabled people.
I'm just as upset as you are about this result, but we have to live with it, at least, for 2 more years and hope the opposition can start working their asses off to swing Congress into a position to keep this motherfucker under control.