I've used Spine 3.4.02, and the latest spine-c/spine-sfml runtime for the following results. I also only render the ship in the setup pose and do not apply any animations at runtime.
When loading up the export in spine-c (using the SFML backend) and not applying any root scaling, I get what I expect
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Setting root scale programmatically
skeleton->root->scaleX = 0.5
I get what i expect as well
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Finally, setting the root bone scaleX to 0.5 in the editor and re-exporting, I also get what I'd expect
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