Apple may win in the end, it's capital vs capital. A small startup trying to steal away that Apple contract from Imagination with a innovative incredible product though; They'd be properly crushed into dust for even dreaming about it.
I agree with all three of your points. Let me take a different tack to see if this makes my point more clear. Apple sued Samsung over rounded corners. The gall of them. As if anyone can own the concept of rounded corners.
Apple shouldn't be allowed to prevent other companies from building phones with rounded corner designs.
Imagination shouldn't be allowed to prevent other companies from building phones with GPU designs.
Clearly, both things happen. There are lots of phones now with rounded corners. Lots of phones with GPUs. But well placed litigation can hobble your nearest competitor or destroy a small one. The result is massive losses of productivity that could have enriched society.
All this thanks to the Capitalist idea that someone can own rounded corners or GPU designs simply because they have the most money. Capitalism rewards those with capital, not those who work hard and add value to society. Those two things are not mutually exclusive, but contributing to society is not a requirement and frequently does not occur.
Theoretically, a single super capitalist or small group of them could corner the market on everything and be rewarded for no other reason beyond ownership. Together, they could stop all progress. With companies like Apple sitting on $200,000,000,000 overseas, but failing to ship a new "pro" desktop since 4 years ago, this theoretical situation looks a lot more real every day.
From Imagination's perspective, rather than changing to different technology, Apple are trying to reimplement Imagination's technology, with ex-Imagination engineers, without paying them.
Whether Imagination are right about this or not, I don't think this is a clear cut case of patent bullying.
They also hold the patents on simulating physics on a GPU and a billion other patents.
Same goes for NVIDIA.
AMD and NVIDIA violate each other's patents all day long and many more they don't sue each other since that would be a legal balckhole for both companies.
But they will we very keen on sueing any new player.
Intel licenses a patent portfolio from NVIDIA currently for legal protections, and Samsung and Qualcomm license their GPU IP from AMD.
The economies of scale and necessary R&D investment needed to be competitive are the primary things preventing new upstarts from making an impact. This is because the industry has matured.
Literally anyone with a couple million dollars can put together an ASIC design team in a matter of months, design a functioning GLES2 GPU which gets acceptable performance, phone up a semiconductor manufacturer, and pay them about half the money to open a run for them. But even for that low bar, there is already an economic advantage to licensing somebody else's chip. When you start getting to higher feature levels and higher performance targets, the amount of real work required to design GPUs is considerably higher.
That said, if you have a few billion dollars to pour into an R&D effort, you can definitely open up a GPU shop, and no GPU mafia is going to be able to stop you.