These next gen consoles are clearly way more capable of creating games that are not possible on previous gen consoles, especially if we talking single player experiences. So after there "we believe in generations" comments the early narrative was the Xbox one would hold back next gen development because Microsoft wanted to go cross gen like you do on PC.
SONY BELIEVES IN GENERATIONS THO 
And with the announcement that God of war as also a cross gen title, the next generation won't begin until 2023 at the earliest on PS5
So then what are you getting on PS5 since a true next gen experience isn't possible on last gen hardware? Well you're getting the PS4 version with built in PS5 system features. And you're being charged extra just to access it
But don't take my word for it, here's what it says on Sony's website about the PS5 versions "upgrades"
- PlayStation 5™ features
- Fast loading: Fast-travel across the map and get back into the game almost instantly with the PS5 console’s ultra high-speed SSD and fast load times.
- Stunning visuals: Experience the vast world of Horizon Forbidden West in stunning 4K and HDR.* From mountain tops to small sprigs of leaves, everything is realized to incredible detail at an enormous scale. Targeting 60fps, Performance Mode further enhances smoothness of movement, animations and controls.
- Haptic feedback: Get closer to each fight Aloy takes on with the DualSense™ wireless controller’s haptic feedback. Feel the sensation of blades of grass you brush past when making a stealth approach, melee swipes you make against machines and armored humans, and the directional impact from enemy attacks when you attempt to evade.
- Adaptive triggers: Enjoy a new level of immersion when you interact with different objects using the DualSense wireless controller’s adaptive triggers. Feel the tension in the string of your bow, the pull of your new grappling tool and the resistance of the triggers on heavy tribal and mechanical weapons.
- Tempest 3D AudioTech on compatible headphones: Listen to the landscapes of Horizon Forbidden West come to life around you with the PS5 console’s Tempest 3D AudioTech. Hear vegetation rustle in the wind, birds flying overhead and large mechanical machines swimming in the water below as you explore environments teeming with wildlife and machines
So 5 bullet points, all of them built in system features.
1. Faster loading - Why are you paying $10 because you have a faster SSD built in?
2. Stunning visuals - Then it goes into detail what it means, it means 4k and HDR, then it mentions 60fps while carefully wording it in such a way so you could speculate mistakenly that it's 4k/60. But you won't be mistaken that they charging you $10 more because you have a 4ktv
3. Haptic feedback - Glorified rumble controls that is standard in a ps5 controller, you gotta pay 10 extra if you wanna use it tho
4. Adaptive triggers aka the same thing, built in system features
5. 3d audio. So they charging you extra again just to use built in features
So the gimmick is they'll add rumble support and dynamic 4k and then they will call it next gen because of that
Sony's own words makes it so you can't lie to me... but only to yourselves
