If they had the real Ralph (and Sue) on the show, I'd totally support it. Having a corrupt cop turned private detective with the Ralph Dibny/Elongated Man name slapped onto the character is an insult, as is renaming Selina Kyle to Sue Dearbon and pretending she's that character, and not obviously a slightly tweaked Catwoman without the whip and with rich parents.
The Flash producers hatred for DC Comics is palatable. Sometimes it works, with Cisco and Caitlyn being 100 times better then their source material. But sometimes its fucking terrible (Ralph/Sue, making Atom Smasher and the female Doctor Light into villains for literally no reason, and almost every other in name only character they've done during the show's run), and is easily one of the worst recurring problems with the show.