Issue is with window tint 'colours' -
Car is stock - came with factory window tint -

That looks very odd - factory tints are obviously all the same colour.

That’s not quite right there.

The door and 1/4 should match the boot glass. Not sure what is going on is it the same the other side? There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
KIA E-Niro 4+
2021 Discovery 5 D300 MHEV commercial

Speaking from experience only thing I can think of is its possible the rear windows might have been smashed at some point prior to ownership and had the lm replaced but used a different brand of tint with different glue etc that's reacted in the sun over time. I had this on a previous car that had tinted windows as standard. The dealer smashed the window and got it replaced at no charge but after a few years I noticed the difference

Hum - yes my thoughts were that factory tints should all look the same
The rear window looks ‘right’ and matches the rear door lid glass
Yes both sides are the same

Looks like it’s a question for the dealer - kind of worrying if the glass has been broken !!

The std LR tint is quite subtle - and can still be seen through from outside quite easily. Some owners put an additional tint on top of the factory to prevent views into the vehicle - this can result in the effect that you have on yours. I’d check the vehicle for an additional tint film on top of the factory tint.

I carry shotguns, dogs and expensive hunting gear in my RR and want to avoid people seeing what is inside - I have done just this ^ but used permanent car shades on top of the tint - it’s impossible to see in, but I can still see out and it gives an extra layer of security 2021 L405 Vogue SE 4.4 V8 DIESEL ~ #17

The factory glass does have this brownish tint on the rear passenger windows from factory.
Something to do with the heat reflecting anti UV glass with built in tint in the glass. For the passengers.
The front windows are a lighter color. But not the brownish color of the rear windows at certain angles or lighting the back windows look different.
This might be because the back passengers are often being driven by their drivers , or carrying their special little ones to school,
so they get a better grade of anti UV light and heat reflecting tint in their windows.

I would say our L405 has the redish hue in certain lights, buts it’s on both the rear door windows and the rear quarter pane. I always through it was just the solar or laminated glass or toughened (not sure what it has). Looks normal dark black most of the time, but certain lights it’s very odd looking.

I will try and get a picture later  Sold - Bell a 2015 MY16 Loire Blue Autobiography 4.4 SDV8
Previously George a 2007 MY07 Java Black VSE 3.6 TDV8
Previously a 04 MY04 Defender 90

Mine is like this when bright sunlight shines right on it. The tint is the same with the loadspace window but the glass is different. I think the rear door glass is laminated or solar reflective whereas the loadspace isn't.

Happened to notice a pinkish tinge to ours earlier but nothing like the OPs pic. Possibly in a different light..... There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
KIA E-Niro 4+
2021 Discovery 5 D300 MHEV commercial

All L405's (& later double glazed L322's) are the same as the OP's!!! The inconsistency comes from the rear doors having laminated double glazed windows, the rear quarter window (side boot glass) is just single layer safety glass so the tint is stable... Unfortunately there is nowt you can do about it sir!