My iPad mini 4 won’t update past iPadOS 15.8.3, how can I update to iPadOS 17?

Yes. Note that system requirements for Netflix and other services will likely be increased at some future point; over the long run, it's likely better to get a new unit instead of the earliest one which can access them.

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An iPad Air 2 or iPad mini 4 isn't capable of 16 or above; they require an A9 or better CPU.

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You can’t download from Netflix because Netflix declided to drop support for your iPad mini 4.

Your iPad mini 4 was released in 2015 with iOS 9.

Now 9 years later, it runs iOS 15.

It had a good run but the hardware just can’t support any further iOS updates.

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