No, it isn’t about how hot the sun gets, although that is a factor. It’s all about the soar wind, which is not air movement like on Earth, but rather charged particles moving out from the sun in a directed direction in a magnetoelectric field.
The Earth has a core made up of a glowing, molten ball of iron, the size of the moon. As the Earth turns on its axis, it throws out its own magnetic field, which is very large for its size, which we call the Van Allen Belt. As sunspots throw out MORE solar wind than without sunspots, this engages the Van Allen Belt, which repel the solar wind around the Earth, and actually cause the atmosphere to enlarge and ward off cosmic rays, which are always present, from the sun, quasars, supernovae, other stars, etc.
When the solar wind is less active during low sunspot activity, the Van Allen Belt shrinks, and the atmosphere contracts. This causes a lot more cosmic rays (which are not a discernible field of moving particles like the solar wind, but coming from all directions), and increase upper atmospheric cloud cover, cooling the Earth—precisely because the hot sun can’t warm it as muich as a clear sky.
makes sense... so, just keep driving our SUVs then...