Have you checked out the mysmartprice review posted here? He checked the peak brightness and it was 800 nits, I'm not saying it's the best thing ever. Their old panels are just bad but this one seems to be legitimately a newer and better one.Rtings is based in Montreal, Canada and they only review the products available in North America.
The reality is that you will never know. Most YT India reviewers will simply provide subjective statements as they don't have the equipment or knowledge to test the panel. I remember few calling the OnePlus panel as mind-blowing when in fact it was an old entry-level Samsung panel. Most of them are paid to endorse, so these products will always get 4-5 out of 5 in all Indian reviews.
To be fair, Mi hasn't been using the best panels for its TVs. The use of misleading marketing terms such as "120 Hz" when it is using MEMC to achieve the same and 10-bit colour depth when it in fact using 8-bit+FRC are meant to make it look better than it is. Wouldn't be surprised if the "upto 1000 nits" is also in an impractical setting.
It simply indicates that it is not a top-end panel since even mid-range Samsung TVs have true 10-bit, 120 Hz support. Also, at the end of the day, Sony, Samsung, LG have also built up software expertise over several years that allows them to deal much better with upscaling and motion smoothing while nearly all Chinese TVs mess up. But yeah, this is intended for people who will go for the size.
And those Samsung ones you're saying with 10bit panels, do they have wider color gamut support than this one? The 8 bit+FRC could be same as 10bit depending on how good it is implemented.
I agree with the 120hz, this TV isn't for gaming.