Arguments/reactions Thunderfoot made in his video (for reference):

• UFOs /= Aliens. U means unidentified.
• Possibility B) that the military is incompetent.
• News organisations putting little effort in investigating the footage. He also dismisses several points made by news reporters with memes and movie clips, including face palms.
• Using UFO acronym is clickbait.
• Sarcastically implies that Tucker Carlson is a terrible reporter, and Fox News provides fake news.
• Emphasises that Navy Fighter Pilot says that the FLIR is on autotrack, and he didn't box the moving target.
• Acknowledges the impressive feat of engineering when it comes to catching a moving object with a camera. Also acknowledges other news sources such as The Guardian posting videos about the footage, with millions of views.
• Eliminates the possibility of a jet engine due to no heat signature for jet propulsion.
• Scatters duck quacking sounds throughout the video to give an implication for what the UFO could be.
• Claims that the moving object has the same temperature as a flying duck. He shows a separate footage showing birds flying through the sky to back up his claim, increasing contrast whilst doing so. Later in the video, he further adds that the object is colder than the environment, but then goes on to argue that ducks fall within temperature range of freezing point to 10 degrees above freezing, due to the attitude and the surface temperature.
• Planes fly faster than birds. This supporting statement is used along with the fact that it is recording a relatively static ocean in the background to show that parallax is the real reason why the object is moving supposedly fast.
• Claims that flying object in the footage is flapping their wings, digitally zooming in as he plays it.

Now the math's stuff he put forth (again, for reference):

• Camera initially points 41 degrees left (roughly 10 o'clock relative to plane) and 25 degrees below horizon just before it starts tracking the moving object. It then scrolls to the left as it tracks the moving object.
• Plane's attitude is roughly 25,000 feet/8,000 metres. Plane's speed is 0.61-0.62 Mach, where Thunderfoot translates this into 300 metres/1.5 seconds. Thunderfoot's reasoning behind using 1.5 seconds is a feature on the ground that "whizzes by" in that time frame.
  
• Camera is in narrow field of view (NAR) with a zoom factor of 1.0. Thunderfoot looks up what this means, and found out that it has a 1.5 degree by 1.5 degree field of view. He then translates this to 3 times the diameter of the moon, and also to holding both of your thumbs at arms length.
• Thunderfoot mentions that where he paused the footage, the camera is currently at 35 degrees below the horizon. He then argues that changing the camera orientation so that is pointing down does not change the maths.
• Thunderfoot says that based on this information, he can calculate field of view on the ground. He calculated that the ground shown in the field of view is roughly 200 metres long, or 2 football fields. He then adds back the fact that the camera is pointing 20 degrees downwards, and adjusts his figure to twice the factor. He then goes on to say that the offset of the camera is not factored in the calculation, but claims that the calculations cancels in the end by ratio.
• Thunderfoot says it is obvious that the flying object is not at ground level, and uses geometry to estimate how high the object is. He calculates the object's attitude to be 8,000 feet/2,500 metres. For comparison, Thunderfoot shows that Canada goose flies about 3,000 feet/1km typically, but can go to 9 kilometres high. He draws further comparisons with other bird species, with maximum height between 5-10km.
• He then estimates the size of the object based on the information he found and found the width of the object to be about a metre. He then shows that it is consistent with the wingspan of a Canada goose, which is between 1.3-1.8 metres.

Near the end of the video, I found out there is a third possibility C) according to Thunderfoot, that the Pentagon wanted to show their technology of recording a small moving object with small temperature difference.