I don't know, but I imagine that even those who are believers in a
supreme being might keep it to themselves to avoid being attacked by
atheists. Like many who do not believe in any significant man-made
global warming, but keep quiet about it for fear of intimidation and
grant denials. In any case, I've read somewhere that even Einstein
believed in a creator. At least toward the end of his life.
It's true that there is a significant overlap between the believers in
gods and the disbelievers in man-made global warming. I don't think
it's for the reason you suggest.

All through history the believers have attacked, even murdered
non-believers, and even today no person who admitted to disbelief could
become president. The reason biologists are not religious is that they
know too much about the complexity of life. Obviously they know that
evolution is written in every page of the book of life, so they are not
going to stand with the know-nothing believers who reject it. They also
appreciate the fact that for all the mind-boggling complexity of life,
even in a single cell, the required complexity of a notional creator is
a different order of infinity.
As for Einstein's belief - forget it. This is a wrong construction put
on his use of metaphorical language.