Comments by "Lawrence D’Oliveiro" (@lawrencedoliveiro9104) on "The Secrets of the Universe" channel.

Occam’s Razor applies. The assumption is that there is nothing special about our little corner of the Universe, so the same laws that apply here also apply elsewhere. The fact that the results we get continue to be (mostly) self-consistent is itself confirmation that the assumption holds true. I say “mostly” because there are some odd things that don’t quite fit. Though nobody has (as yet) come up with a new, yet self-consistent way of explaining them.
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The name “Milky Way” is also a bit of a giveaway ...
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Notice the “evolved” part of the description of these galaxies. That means they have already accumulated significant amounts of elements heavier than H+He.
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... and it turns out we’re at the unfashionable end of it ...
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