You know how it is with the US defense analysts. The Russians don't have money for anything and need to beg India or the UAE to fund their military aircraft which will never be built. When they are fully funded by the Russian Federal budget. While the Chinese can't develop anything on their own without copying. Yet they come up with the J-20.
But if you look at their own US weapons programs you will find that the US themselves use a lot of money buying foreign expertise. They bought the Yak-141 patent on the VTOL scheme for the F-35B. They cooperated with Rolls-Royce to make the LiftFan for the F-35B. The Constellation class frigate design will be bought from Italy. So, even the "mighty" US military industrial complex can't do everything on its own.
Ignorance, arrogance and complacency. These are the reasons why the US is losing its clear military edge over China and Russia in just over twenty years. The US has hardly developed any innovative systems during the time period while China has made huge strides closing the gaps. On the surface, it might not look very obvious, but that's largely because it is overshadowed by the US's large existing stock and huge quantity lead. But if you look deeper and examine the capability and quality gaps, it's clear the gaps are significantly narrowed. In some cases, the US is even behind.
Still, there are people who have noticed it. For example, this video blogger asked why the US is falling behind China in all kinds of missiles: ASBM, hypersonic missiles, air-to-air missiles, etc.
Traditionally, the US has relied on air dominance over its adversaries to fight the war. But it's hard to argue today or in the near future the US still has that clear air superiority over China, at least in terms of aircraft capability. On the other side of the equation, the US doesn't really have advantages over China or Russia in air defense systems. Its carrier-centric navy is also facing challenges from ASBMs and hypersonic anti-ship cruise missiles. In other words, the challenges to the US military is not just platforms, but potentially also doctrines.
The only area that the US still has clear dominance over China is in nuclear submarines.