No, most older supercars have net lift front and back, not downforce. Another way in which the Hellcat is superior. The rear spoiler provides actual downforce combined with the body shape at the rear end.
I have done the research and went over, at one time, an entire website devoted to debunking the claims of big downforce claimed by exotic/expensive carmakers. Ferraris, Lambos, Aston Martins, all the big makes. The cars were actually taken to the same wind tunnel and actually TESTED. The results were DISMAL.
But "far more downforce" is a myth, if not a downright fantasy created by braggadocious false ad copy or sales brochures. Even the Pagani which boasted about how much downforce it had was found to have FAR FAR FAR less downforce than it claimed, and that was their big hoo-rah selling point (what did they claim? Ten tons of downforce at 3mph? I don't remember.)
But, most supercars are not bought for their performance. Most buyers don't know the difference between brakes made of carbon-ceramic or carbon-carbon, or how carbon-carbon brakes are even created, or why those who know what they are talking about say, "carbon-carbon" instead of just "carbon fiber" or "carbon" brakes.
The supeduper Herbootyaccess 3000 supercars are purchased for other reasons, and most are never even gotten within 10 percent of their actual capabilities, so they don't find out how low-performance the cars are. I am not decrying that. People can do what they want with their dosh. SOME people, especially on THIS forum, actually work hand-in-hand with people who produce actual performance-enhancing results with their businesses. It's hard to argue with single-digit timeslips, and no amount of sales brochures at some supercar maker's showroom can shout louder than a win light in your lane.