Not having watched much of the show, is my impression that the showrunners are doing to Felicity what Smallville did with Lana Lang?
As pro-Lana and anti-Superlicity I might be biased but...
Felicity's case is worse because unlike Lana who was liked only by the creators, Felicity gets support from Guggenheim and the fans (some of which are the biggest psychos in the world). Also, Lana at least was a canon comic character and important to Superman mythos.
Felicity however has had her role and abilities being blown out of proportion by practically making her the smartest person in the Flarrow verse even though she was an ordinary IT girl in s1 and the STAR Labs team is clearly beyond her capabilities. Like who the fuck can make virtual autopsies out of nowhere or know more about bombs from the Internet than a former soldier?
She also lacks much characterization beyond "being awkward, unbeatable at anything and wants to bone Oliver". No depth shown and s3 has been basically her doing the opposite of what Oliver wants so that there can be some tension.
She constantly gets praised for being amazing and great and superintelligent from the Arrow to The Flash villains. She never gets called on any bad behaviour and has been put as the moral compass of the team even though she was the first willing to leave.
This and many other examples are of course because of her fucking fanbase that wants even more of her (and the creators don't want to damage Saint Felicity by tainting her with any flaws) and make dozens of people close their social profiles by bullying them and the creators just keep giving in to their wants, effectively retconning and ruining the show as well as practically making the whole marketing campaign center on Felicity/Olicity.
Words can not describe what rot has followed Felicity's popularity and the writers' decision to keep pandering to that fanbase for the free marketing instead of writing a show about vigilantism.