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Don asks:

"Do you still believe Einstein's thought experiment even though it ignores some basic physics?"

It appears you do not understand this at all. The principal of equivalence is basic physics.

The drawing on page 36 of my book Physics: Decade by Decade may help you understand. Because of copyright restrictions, I can't reproduce it here or post it on line, but the caption alone may help.

Here's the caption, which appears on page 37:

Einstein generalized the theory of relativity to include relative accelerations with thought experiments like this one. An observer in the lab sees an astronaut following a parabolic path downward like a falling ball on Earth, while the astronaut sees the observer to be following a parabolic path upward. They can make no measurements to distinguish whether the astronaut is falling under the influence of gravity or the laboratory is accelerating upward at that rate. Thus a gravitational field is equivalent to an accelerated frame of reference. Pursuing this idea led Einstein to combine space and time into a four-dimensional spacetime that distorts in the presence of mass. He concluded that gravity is the result of that distortion, and thus affects light as well as matter.

[Self serving statement alert:] I suggest you buy the book.

Fred Bortz -- Science and technology books for young readers (www.fredbortz.com) and Science book reviews (www.scienceshelf.com)