S9 user here. As others have recommended, wait for the iPhone 12 announcement and then decide. Even though I've not owned an iPhone, I'm inclined to recommend it over S20 or any Android device. Since you're using an S8 and talk about the price, it's safe to assume that you will hold on to your next phone for a similar if not longer amount of time. As such, you might find my experience useful.
I was very happy with my S6 Edge+ (even after it began to slow down <2y mark) until I cracked the screen and everything just added up. So after much research I went for the S9 as the iPhones then were considerably more expensive and didn't seem to offer what I wanted in terms of design, photography, headphone jack etc.
However, the wow factor that was there when I upgraded from the OG Moto G to the S6 Edge+ wasn't there this time. The camera was the biggest let down. Yes, it was able to capture more light, but the image processing and lens seemed off in comparison to my previous phone. So much so that while taking photos around NYC last summer, I used my S6 Edge+ more than my S9. I'm one of the minority who prefers lens accuracy over the trade offs in the wide angle trend of recent years, so there's that. Additionally, the S9 photos seem over processed, not to the level of Chinese brands but IMHO the photos had lost the photographic charm which I enjoyed with my previous phones.
I do understand though that photo quality is subjective given that all flagships deliver similar performance across the board. If you were to buy solely on the basis of cameras, I think the Pixels win, but that product line is erratic. So my ultimate recommendation after much writing is based on overall user experience and value for money, and I believe Apple really delivers here better than the others. I've slowly gotten more into the Apple ecosystem - phones were the last hold out; but it seems that at long last the iPhone is arriving at that magical sweet spot of the confluence of price, design and specs. Add to it the phone's longevity and retention of value and you have a purchase which you can enjoy as much in your 3rd, 4th and maybe even 5th year as you did in your first. This is based off my 2014 MBA and 5th Gen iPad. I've typed this on my 16" MBP.
This is my first post and I apologize for the verbosity. Thought I'd pitch in with my experience though seeing as I'm in a similar boat



Also, 3 photos from my S6 Edge Plus that I miss dearly since losing it last year.