[Law]

Nissan/Infiniti had something good going in the early 2000s with the FM (Front-Midship) platform that was a modular RWD based platform sharing the VQ and VK engine family. Not only did the modular aspect address financial concerns in the wake of the crisis Nissan faced internally, but it also was a good recipe for nice RWD cars that could be leveraged by the Infiniti brand.

The products that came out of the FM platform: the Nissan 350Z, Infiniti G35, and Infiniti FX35 in particular, were highly successful models and all except the latter were available with manual transmissions and performance configurations (i.e., Brembo brakes, RAYS wheels) from the factory.
No, it wasn't Evo or STI types of performance nor was it a raw visceral S2000 type experience but it catered to a little more of that JDM sports GT oriented concept.

I've said this many times since the late 2000s but where Nissan/Infiniti missed their golden opportunity was with the GT-R.
The GT-R was a based on the PM (Premium-Midship) platform, which was really just a further development of the FM platform and the VR engine's block was ultimately built off of the VQ architecture (VQ35HR) as a starting point.

There were several key mistakes to the whole GT-R project, development, and marketing that in retrospect came at the expense of the Infiniti brand:
A) Nissan developed and positioned the GT-R to perform way out of its league (as a brand) and targeted the 911 Turbo instead of the category where it would've naturally shined & helped with brand development which is to compete in the premium sports (i.e., BMW M3, CLK AMG, 911 Carrera, RS4) segment.
B) The decision to badge and sell as a Nissan instead of Infiniti
C) The reluctance to trickle-down engine/drivetrains to the Infiniti brand to allow other higher premium performance models to exist.

The GT-R marque, by all accounts, is an iconic car to the Nissan brand.
I completely understand why the final decision was made to badge it as a Nissan globally and why they would want to shoot for the stars and make this 'supercar killer' for less than half the price of those cars. It was a pride issue for them, but this pride is also what cost them their future in the premium space.

The GT-R originally was just a high-performance version of the Nissan Skyline, which was a sort of premium sedan/coupe with RWD or rear-biased RWD and an Inline-6 engine in higher-spec models.
The Skyline coupes & sedans sound a lot like a perfect BMW 3 Series competitor to me.
And that's exactly what they did with the launch of the new V35 Skyline in the 2000s, which launched as the Infiniti G35. Gone was the Inline 6 (replaced by a V6) but you still had a relatively balanced FR platform with sporty characteristics.

Naturally, you would think that the GT-R performance variant of the Skyline would take that up a couple of notches and be able to compete with the likes of BMW M3s.
But this is where Nissan got too ambitious.
The Playstation & Need for Speed generation had high expectations.
They were used to tuning Skyline GT-Rs in video games to 1000 HP overnight that would eat supercars for breakfast, lunch, and dinner.
Nissan thought there's no way they would accept anything short of a car that would outperform the best supercars from Europe.

And with that, the decision was made to split the GT-R from the Skyline (Infiniti G35).
Yes, the GT-R would be loosely based on the same platform as the G35's FM platform, but would basically be an entirely different car in a completely different league.
Still, an Infiniti GTR as a halo would still provide the perfect boost to the brand.
What Infiniti needed during the 2000s was that icing on the cake.
It was finally gaining traction and respect as a real premium contender after being that awkward turtle left behind in the 90s (when its competitors Acura & Lexus took off).
Car enthusiasts in North America always ridiculed the likes Acura for badging icons like the NSX and Integra Type R as Acuras instead of Hondas, but it's effective in several ways from a marketing and brand building perspective:
1) it's effective as a performance halo for the brand, cementing the performance/premium/quality image into the customer mind, and
2) it creates a better buying/ownership experience for the customer who is spending a lot more money on the NSX than somebody buying a Civic. This exclusivity and premium experience sounds snobbish but it's the experience that sticks with these high-paying customers. The training, service, and distribution model that goes with dealing with a premium customer is different than a customer looking for 0% APR, a good warranty, and fuel economy.

Imagine if the LF-A came badged as a Toyota. It just wouldn't make sense...for someone selling a Prius to offer the same experience. It just wouldn't make sense to train the dealership's mechanics who do 4-cyl oil changes all day to all of a sudden deal with a dry-sumped V10.

So when Nissan decided to badge the GT-R exclusively as a Nissan worldwide, it basically made a conscious decision to orphan the Infiniti brand, its dealers, its distribution network, its mechanics, its entire brand.
I remember the articles and news surrounding the dismay of Infiniti dealers.
How could such a great opportunity be wasted?
It's not like enthusiasts wouldn't know it's a Nissan anyway.

But alas, that's what happened. And for years, Nissan withheld the VR engine family & DCT from further development outside of the GT-R.
With an aging drivetrain lineup, the Infiniti brand had to use the same recycled VQ and slushboxes until very recently when a smaller displacement VR30DETT turbocharged V6 was finally allowed to exist, but by then it was way behind the curve as the Germans (namely BMW) already had several generations of turbocharged 6-cyl development under its belt.

So Nissan really has nobody to blame but themselves.
They knowingly neglected their Infiniti brand to protect their beloved GT-R, its name, its drivetrain, its street cred.
Perhaps GT-R enthusiasts are happy that it didn't get 'watered down', but it comes at a cost to business.