So your reason for not buying a Samsung phone in the future is that you're... Unhappy with a beta that is not available in your region, won't even be released for your device, a beta that you've got a cursory overview from a video?
I imagine people want more than tweaks. Overhauled animations, enxynos battery optimisations, new and improved ui elements, android 12 selling points like material you are all what people were expecting, and its not hard to see where they are coming from. Oneui as stayed fairly consistent for 3 years, which isn't a bad thing, but now is a time for a mixup, and without many new changes or features of note, they are going to be left behind.
I currently don't have the beta, hopefully in the next few days, but the overview is really all there is. Android 12 is big, and oneui has had a few years of marginal updates, and its really quite disappointing if this is what we have, with little new features of note, and really no changes to ui look or feel.