Unfortunately, Bitcoin is a very inconvenient coin for payments due to the long time it takes to confirm a transaction. If an analogue of the system as it was implemented in El Salvador is implemented there, then I don’t see the point. It’s probably easier to make a crypto exchange and crypto debit cards, and tax these operations.
Bitcoin scalability issue can be mitigated by moving to Layer-2 solutions like LN, which addresses the scalability issue and also reduces the fee. The real issue in bitcoin adoption is that government's not willing to allow any financial system to operate which they can't monitor and manipulate. What we have seen so far is that government's are adopting only centralised Bitcoin, i.e., bitcoin going through centralised exchanges with KYC.