I find this issue to be a matter of some cultural blowback and disconnected logic. I've heard it over and over -- especially during the campaign season, but earlier as the "extended campaign" proceeded.
Mark Twain made a pile in speaking engagements and there was never a problem with it. In the case of the Clinton's they made this money from writing books as political celebrities but also in taking large sums for speaking engagements. This wouldn't be so much a problem if they weren't working a revolving-door in politics, because, as Fortune notes, "It's hard to come across as a credible critic of Wall Street when your bed is feathered with six-figure speaking payments to [sic] to investment banks and private equity firms." [Here I notice again a decline in our discipline of language through the years, because the writer obviously meant "from" investment banks etc. and not "to."]
So the paragraph about "What are the Risks?" can only cite an "appearance of problems" likely meaning "appearance of impropriety" as it's called in statute and regulation.
In this respect, one wonders what actual plans the Clintons had in re-entering those revolving doors. While Bill continued post-presidency his Foundation, book-writing and speaking engagements, his wife ran for US Senate. And again, after that, she capitalized on the celebrity. Both of them might have decided to temper this matter of personal gain if they'd actually planned to re-enter the door of politics.
Earlier in the article, it mentions emoluments she received as a lawyer and corporate director as Bill began campaigning for the presidency. To me, this seems like nothing in the way of impropriety. Unlike other political wives, it was almost as if she was determined to strike out on her own path, despite Bill's success.
What I object to is the idea that political leaders -- who are well-paid for certain reasons -- are supposed to adhere to a sack-cloth-and-ashes lifestyle. It's OK for Trump to run his private-sector empire out of the White House (but it won't be OK), but it's not OK for a celebrity-politician to profit from books and speaking engagements, even for "representing" the Great Unwashed.
Our system is corrupted with money, Citizens United only the latest twist in the phenomenon. You could think that public life should be a market exclusively limited to a currency of votes, with private capitalist pursuits exclusively limited to a currency of dollars. We know better.
To be good at a job or a career pursuit, practice makes perfect and experience matters. Unfortunately, if you want to play the game that the GOP's most loyal inner-circles have supported over the last century, you will get mud on your boots.
Trump is about to muddy his own boots by dragging in the dirty dogs of his business life to foul his public life, and that is an unfolding theater showing now only as preview. If that weren't enough, he's dragged our political dialogue to the level of WWWF Smackdowns with outrageous language and ideas, inconsistencies from one appearance to the next, a flamboyant personal appearance and a disgustingly self-absorbed, egotistic, narcissistic personality and appearance inside and out.
By the way. Trump and his business. Has anyone seen a Bob DeNiro film entitled "Heist," in which the actor portrays a casino-magnate named "Pope?"