The commander in the video did not describe it as being like a reflection. Why don't you watch his 6-minute testimony and then offer an informed opinion?
> flight computers tracking the glitch would plausibly show it "performing maneuvers" that make no sense for physical objects, such as the ones you describe.
This is an example of "coming up with less-extraordinary theories that contradict the evidence," as gfodor said[1], because you have asserted "glitches" in "flight computers" and ignored the pilots' eyeballs, which corroborated the radar contacts that had been observed over several days.
As for pilots' eyeballs- nothing I've read about this clearly states that anyone got close enough to get direct-eye-contact; most mentions of "visual" confirmation are talking about via cameras (and to me, the footage I've seen of it looks precisely like a camera artifact.) Also I wouldn't discount the possibility of a pilot, squinting to see a small distant object that his expensive flight equipment is insisting is there, simply hallucinating- humans are suggestible, and just as vulnerable to "sensor fusion" errors as prototype military hardware.
Radar Contact + FLIR Contact (videos) + Human Eyeball confirmation by two types aircraft + multiple eyewitness testimony != a technical anomaly nor a hallucination
Watch this video of a U.S. Navy F/A-18 squadron commander (not an average military pilot) who intercepted one of the objects and engaged in aerial maneuvers with it. He describes intercepting the object, flying about one mile away from it, with the object demonstrating awareness of his presence by mirroring his maneuvers. Then he flew aggressively at it, and the object responded by rapidly flying away. It then showed up on radar at the position he was returning to, where he had been flying a combat air patrol before he was sent to intercept the object, indicating that the object had been aware of his aircraft all along.
The commander also said that the flying object appeared to be maneuvering about 20,000 feet over an unknown object which was submerged just beneath the ocean surface.
https://youtu.be/jCaruUtiPHo
Other testimony recounted at https://www.thedrive.com/the-war-zone/27666/what-the-hell-is... mentions that the ships had been tracking these objects on radar for a few days already, with them appearing suddenly on radar at 80,000 feet, rapidly descending vertically to 20,000 feet, and then flying straight up again, disappearing past 80,000 feet. The ships went to non-drill battle stations while the aircraft intercepted the object.