That's like saying there's no point to Jailbreaking an iPhone anymore. I had the 6 Plus and JB was an absolute must have, the iPhone 6 Plus was horrible plain jane stock out of the box, where the JB unlocked features and customization that are a necessity on a smartphone.
The Galaxy S4 which I owned back in the day, was one of my least fav Android phones, the stock Touchwiz on that phone was horrible, just so bad. Rooting and custom ROM's could turn that S4 into a GPE phone, meaning it was then running stock vanilla Android, and still officially supported by Samsung + Google. But even good Touchwiz ROM's made the S4 night and day a better device.
My old Note 2 on custom ROM's was ten million times a better phone, than running it stock out of the box.
Actually out of the 17 different Android phones I've owned since 2009, every single one of them I root within the first day, and typically install a custom Recovery within it''s first week. I just like the extra customization and complete total control over my gadgets, that Rooting + JB offer., I am not happy with just a stock device out of the box. It's like a car too, on an ///M5, I like my tinted windows, lowered suspension, new exhaust, new tires, upgraded suspension, short shifter, engine tweaks, etc...