Lightning is indeed NOT a fork of a Bitcoin, it’s essentially a Layer 2 for Bitcoin (if you think in terms of the Internet’s TCP/IP model). It solves pretty much every use case created by any Altcoin when competing with Bitcoin, as Bitcoin chose security and decentralization over scalibility in its base layer (on-chain).

As for buying Monero, I only deal with Bitcoin, but I’m pretty sure you can easily buy Monero still as long as you don’t use centralised exchanges (permissioned), and instead use Decentralised ones (permissionless). That’ll be the case for any altcoin that still has decent popularity for the foreseeable.

Not exactly. Lightning makes it super cheap and instant.

Bitcoin is pseudonymous - Transactions are transparent, yes, but the addresses are not linked to any PII - The exception comes in when the user uses a Centralised Exchange that does exactly this, it bridges anonymous addresses with PII via KYC.

Bitcoin can be sold anonymously using P2P DEXs (decentralised exchanges), where the fiat transaction has no link to Bitcoin.

That’s assuming they even would want to sell.

All in all, it comes down to how the user uses the tool. Bitcoin can be as privacy preserving as anyone wants. But if they KYC, they can kiss any privacy goodbye, and really, that’s the misunderstanding that has reached most non-Bitcoin users these days. Experiences based on a lack of understanding.