Let's say we run into some other species will they accept a 95% premined supply?
Yeah, brother, they will also accept PS5, Supra car, and big OLED (haha), what a non-serious question, like you should ask yourself, if there is any aliens (which are not any) why would they care to be interested in BTC because most of the people interested in BTC are want to become rich and i don't think aliens have such intentions, but who knows, we have seen so many sci-fi movies on aliens and in space and sometimes i wonder a male alien might be beaten up by his wife alien too (haha),
Well, there is not a single factor that comes to my mind that will convince them to use BTC for buying or selling something, or in any intentions so, my advice to you is, to change the type of ***. (i hope you might understand).
if they need a car why would they buy BTC well, if aliens are true then it's mean wormholes are true and pause of time is also true so, that's a good point for aliens they could buy 1 BTC from here and can go to another dimension where time goes slow and after 1 year they came back, and it's been 100 years on earth, they would definitely be rich by then and they can buy another shuttle (haha).
perhaps some advanced civilization from the outskirts of the deep space have figured out how to live harmoniously without killing your kin for resources or money. Perhaps they don't have the concept of money and are literally doing the barter method since time immemorial.
Or perhaps they could steal anything they want (haha) or perhaps they are extreme autotrophs who mostly depend on others for everything (food, like animals),