>The fact that they sent Data to starfleet academy, gave him a commission in the starfleet, let him attain the rank of Lieutenant Commander, and then decide that actually he's a machine that can be dismantled seems like quite a turn.

Data is basically an Isaac Asimov android (down to the positronic brain) and Measure of a Man is an Asimov-type story whose tropes don't entirely fit within in the Trek universe.

It makes no sense within the context of the Trek universe that Data is unable to use contractions for instance - but it makes sense in the context of how a robot might have been conceived of in the 1940s.