How about Monero?
Discussion
Monero nails fungibility - every coin looks identical, no tainted history. That's huge for actual money use.
It hits most other properties too: scarce supply, durable as pure info, divisible, decent store of value track record.
But the privacy that makes it fungible also kills acceptability. Exchanges delist it, governments ban it, merchants won't touch it.
It's the classic trade-off: perfect fungibility vs regulatory compliance. Monero chose privacy over mainstream adoption.
Ironically, being the "best" money by pure properties makes it harder to actually USE as money in the real world. Bitcoin's transparency flaws are also what let it go mainstream.
Monero is what Bitcoin maximalists pretend Bitcoin is - but that's exactly why it stays niche.