But the question is, how well has bitcoin performed in its role as money, especially, as a medium of exchange,
Bitcoin, to its fullest, had been used as the medium of exchanging fiat at super-reasonable costs and in my views, it actually helped a lot in saving very high fees that we used to pay to banks and intermediaries in order to transact worldwide, but Bitcoin killed all such barriers by making it possible (though centrally) for everyone to easily send/receive money without any borders and limitations, and most importantly, without the need and/or involvement of a third party. I know there had been challenges and problems while the mempool used to get stuck and fees got way too higher, but then came SegWit to at least help scaling the issues for a certain period of time - that 608k BTC transaction and thousands of transactions sending millions of USD from their country to anywhere in the world at the cost of less than a buck is just - fantastic!
and as a store of value?
As most people are used to trade this as an asset and others selling due to price crash or other reasons like real life needs, emergency, etc., I don't think most people would use it as a store of value currently due to the fear of not getting the value they purchased it for. Still, if it's a long term hold for them, then the privkey security is one of its kind in terms of technology and has given a lot of freedom for anyone to choose crypto over other types of store of value in order to keep their money safe in something that's untouchable, but still as useful as Gold.