Most are inhospitable — too big, too hot, or too cold for any conceivable life form.
Whoever wrote this has obviously never read any science fiction. ;-) The term "conceivable" covers a very wide range of planets (and various environments not based on planets) in which intelligent creatures might evolve.
Some years back, I read Robert Forward's Camelot at 30K novel, about a human expedition to an inhabited Pluto-like planet out in the Oort Cloud; the title references the mean temperature of that world. Part of the story was a quite imaginative method that the world's inhabitants used to colonize other large rocks fbig enough to have useful gravity and far enough from any star that their sort of life was possible. That turns out to be most of the galaxy, of course.
Going back even further, to 1957, we find Sir Fred Hoyle's novel about a dense cloud of gas (similar to what's called a Bok Globule) approaches our Solar System, and instead of passing through, settles into a small, dark ring around the sun. As the catastrophic effects on Earth settle down, scientists discover that the cloud itself is an intelligent creature that just stopped by for a meal of photons and assorted small molecules emitted by the sun. It is, of course, surprised to find itself being contacted by intelligent creatures living in such an unlike spot as a planet, since you'd expect true intelligence to evolve only in the rich clouds of interstellar space.
I'm sure that many readers of this forum can list many other literary works that depict life in environments not the least bit like ours. Anyone who can only conceive of life on a planet similar to ours is seriously lacking in imagination. But there are thousands of writers who aren't so mentally crippled, and millions of readers to read their work. ;-)