All I've asked is for you to engage in a discussion about one of them. Then I offered a chance to discuss a different one. I have no need to view the web site of a scientist who turned propagandist. No one needs you to post (Gish Gallop style) large blocks of his text.
Talk about the speed of light, or don't. It's completely up to you. But until Ross starts posting here, I'm not discussing it with him, only you (or other posters).
Visible light is necessary for photosynthesis.
Each photon of infrared light has too low an energy for photosynthesis and is harmful to life.
The intensity of light emitted by a given object depends on its wavelength or frequency. How the intensity changes as a function of frequency is called the spectrum of light. The spectrum of light emitted by a star is determined by its surface temperature, which is, in turn, influenced by the energy generation rate in the stellar core and by the surface area.
The energy generation rate and the surface area are, in turn, determined by many physical constants such as the magnitudes of strong interaction, gravitational interaction, and electromagnetic interaction, and by the electron mass, the proton mass, and the speed of light.
We can divide main-sequence stars into two classes: blue giants and red dwarfs. Blue giants are massive stars, and energy generated in the core of a blue giant is transported by propagation of light through the stellar interior. Because blue giants emit copious ultraviolet light, they are not suitable for supporting life.
Red dwarfs are low-mass stars, and energy generated in the core of a red dwarf is transported mainly by convection. (In a heated pot, energy is transported from the bottom to the top by the convection of water.) Red dwarfs emit mainly infrared light, whose energy is too feeble to support life.
In terms of their characteristics, sun-like stars fall between red dwarfs and blue giants: both convection and radiation play roles in transporting energy in such stars, and they emit most of their energy in the visible band, which supports photosynthesis.
Because most stars happen to be situated near the boundary between the blue-giant regime and the red-dwarf regime, a slight change in the value of one of the above-mentioned physical constants one way or the other would push all stars to become blue giants or to become red dwarfs.
In order to have sun-like stars in the universe which can sustain life, the values of these fundamental constants, and the speed of light, must be
fine-tuned.