I didn't know vacuum tubes could glow blue, so I asked ChatGPT.:This is closer to what you would see in reality:
Vacuum tubes glow blue due to a phenomenon called Cherenkov radiation. When high-speed electrons pass through a vacuum, they can exceed the speed of light in that medium, emitting blue light as a result. This effect is commonly observed in certain types of vacuum tubes, such as cathode-ray tubes (CRTs) used in old TVs and computer monitors.
Imo, this is impressive. I wish tubes were the like one of these fashions that comes over and over, and factories start producing them again. I know there are some in production, but good old nos quality I mean.