Because the phones where available in US and Europe and now they won’t be?
That’s a major change. You can say the company was changing over time, but a move like this is a major change.
I don’t understand how you’d think this wasn’t a major change.
It would have made much more sense to kill those other brands in the West and unify everything under the OnePlus banner.
Also I think the iPhone and MacBook brands are much stronger than Apple itself.
Oppo, Vivo and Realme sound like those weird dropshipping Amazon brands. Or the whitelabel brand Android phones you can buy on AliExpress. If I didn't know they are legit brands I would genuinely think you'd be trying to sell me a scam phone that fake-advertised having 12GB memory or a Snapdragon.
Realme is literally an ID verification system and a terrible choice for a brand.
OnePlus was on the decline and it was clear it wouldn't be a contender for much longer here in the UK, especially when they merged OSs with the OPPO (?) OS, and software quality went through the floor. I moved to Pixels and currently have a Pixel 9 Pro XL which I'm looking to change as they destroyed the battery life with the march update and it still hasn't been resolved. The Pixel has been solid otherwise and performance is still excellent, but I can't abide having my phone entering battery saver every day by late afternoon.
Nothing(TM) looks like it could be a decent choice, but they're generally weak hardware compared to a 9 Pro XL class device, and I'm not a fan of Samsung any more as a company, though it seems a S2X Ultra might be the only real option.
Somewhere along the way, the Pixel caught up, and the other quirks of the OnePlus diminished the relative benefit (I recall having some issues with their Android variant, and their charging system not actually following the USB-C spec in a way that was causing me issues). As someone who generally doesn't care about smartphone specs aside from "can it last all day?" and "can I take decent pictures without giving it much thought" the OnePlus line was briefly a great option, but hasn't done anything to make me want to try another one in a decade now.
I can't speak much to other flagship phones; I'll never own an Apple product and my experiences with Samsung's software across other devices means I'll likely never consider them either.
Even the Nothing Phone (4a) Pro is getting close to the price of an S26 here and the S26 will absolutely blow it out of the water when it comes to pretty much every facet of the hardware.
Pixel 9/10 Pro XL is a midrange SoC sold at flagship prices. Even the A57, which is a midrange Samsung model that will soon hit 350 Euro is faster single core than the Pixel 9 Pro and on par multi-core. Also has better battery life and despite only being 0.1" smaller weighs 42g less and is much thinner. Gets supported for 6 years and also gets monthly updates. Also doesn't die frequently with spicy pillows, camera bars that drop off, etc.
I still buy Pixels because it has an unlockable bootloader and can run GrapheneOS, but Google's pricing is insane and I wish that they would go back to the old price points. The 10a is the only Pixel with somewhat reasonable pricing for what it provides, but unfortunately they made the hardware differences larger than in the past (e.g. be not upgrading to the latest Tensor SoC).
(And seem to be doing so successfully - certainly, you see a lot more Nothings than OnePluses in London)
I also think of Essential and Poco when this kind of thing comes up.