This was a result of the state of Voyager literature during a period of time when there was a great deal of crossover of characters in many of the novels, as well as the creation of a very large story arc that culminated in the Destiny novels and whose impact continues to be felt.
Voyager had four novels released shortly after the series ended, all written by Christie Golden. Over the next couple of years, the choice was made to focus on Voyager's 10 year anniversary by releasing a trilogy, set during the run of the series, and an anthology of short stories. That was the "String Theory" trilogy, and Distant Shores.
While those projects were in the works, however, the other series were continuing on and particularly in TNG books, Titan books, and some notable stand-alone novels like Articles of the Federation, Voyager characters like Janeway, Tuvok, Seven, and the Doctor were featured. They were interesting characters who were available, as there were no other stories in the works to contradict these appearances, so editors and authors decided to make use of them.
Once the 10 year anniversary projects were done and it became time to again look at moving Voyager's story forward in the present timeline, the larger Borg arc, beginning in the TNG book Resistance and continuing through to the Destiny Trilogy was in the works. Margaret Clark, the editor in charge of the TNG part of this made the choice to kill Janeway in Before Dishonor. While I know it might seem wonky from the outside looking in, at the time, it was hardly an unprecedented thought. Janeway's death was seen as a part of a much larger Trek story involving the ultimate transformation of the Borg. And in the years right before Before Dishonor, Janeway and other Voyager characters were all over the Trek landscape, so Margaret was essentially continuing with the status quo at the time.
It is common practice for editors of Trek who work in one series to respect the work of others. So when Marco was tasked with taking Voyager forward post-Destiny, it was normal for him to take what Margaret had done in Before Dishonor and build upon it rather than ignore it or try to change it. Margaret's idea was embraced because in addition, it created an opportunity for us to tell a story that had never been told before...how would one of our crew's react to the death of their beloved captain?
Yes, other important characters in Trek had died before, but I don't remember any stories written around those deaths that dealt with their impact in the same way the Voyager relaunch has done.
So, I guess the short answe that everyone hates is that Janeway's death created an opportunity for us to tell the most compelling and interesting story imaginable, given all the choices that were before us at the time. That it happened in a TNG novel, rather than a Voyager novel might be disconcerting, but is hopefully easier to understand when you see the decision in the context of everything else that was happening at the time.
KB
), maybe it's possible to create a role for her which gives her a possibility to be the one in charge of the ship. As I see it, making her an Admiral was a big mistake from those in charge of the TV series. Janeway's destiny is to explore space, not behind a desk.
