Apple is pioneering better SOC than anybody else.
But apart from that you are perfectly right, none of the big 3 companies are actually pioneering anything anymore.
Google never was, but leaned on 3rd parties that made some very good Nexus phones, ending with the Huawei made P6.
Now the pioneers are mostly Chinese, while Samsung seems to be falling behind.
Google Pixel was never a front runner, iPhone was traditionally in some areas mostly software, while Samsung was in both software and hardware.
If you want the coolest newest stuff, it seems China is ahead with Xiaomi, Honor, Vivo etc.
The Samsung S25 Ultra is still absolutely a great phone, and I think recognized as the leader to beat, as a well rounded high end package.

Regarding camera I think it’s getting damned hard to say which is best, comparison tests with many photo’s seems to swing between one phone maker to another, and movie stabilization also vary, even with good camera.

I think Samsung is still clearly ahead of Google and Apple, and the Chinese phones too have strengths and weaknesses. I like Xiaomi a lot in their flagship killer range, but on the top tier, they still have problems with camera stabilization Samsung handles better IMO.

The thing that impresses me most, is how much phones still improve in a single generation.
Maybe not enough to ditch the old one, but definitely enough to make the new model worth considering even when you can get last years model at a pretty hefty discount.