The Bitcoin symbol was added to unicode 7 years ago, those were wildly different times. The Bitcoin symbol was the de-facto symbol of all digital money back then (eth had just been released a year prior). Also there was no arguing what symbol the Bitcoin symbol was.
It had a caché that we will never see again in the world of digital currency symbols, and it rode that caché in to unicode inclusion. A one off.
Now in 2026 (and moving forward) there is no way a Layer2 digital currency symbol is going to get in there. And definitely a symbol that doesn't have universal agreement for what it's supposed to be for. Even for Layer1, there's just no way, at least if we're being honest.
That's why Tether chose ₮, Tezos chose ꜩ, and so on.