However, if you don't limit the market to just one coin, then scaling becomes much more solvable.
i disagree. it is not about having more coins (different altcoins apart from bitcoin) to handle more transactions it is about handling what transactions? it is about adoption, the adoption by merchants for example. a merchant is never going to add 20 different payment option to his shop just because there are 20 different cryptocurrencies. it not only makes things hard and costly for the merchant but also it increases confusion for his customer. studies show that people will get confused when there are more than 4-5 options. and there are already enough fiat payment options everywhere. if a merchant wants to add crypto they will add 1 or 2.
But since LN can be implemented on top of any blockchain that implements segwit,
LN does NOT need SegWit. Lightning Network works based on a couple of technologies such as Hashed Timelock Contracts, Multi Signature and 2 more which i can not recall. many altcoins have these or can add if they don't.
what SegWit does is that it makes it all much easier and safer by fixing malleability for instance.
I think the true power of LN is not scaling bitcoin, but creating a multi-coin payment platform for crypto in general. I know Litecoin has LN, Stellar is planning to add it, and I think maybe a few more coins as well. By having multiple coins use LN, and since LN has cross chain swaps, that would make the scaling problem of any single coin much less. Instead of filling up the Bitcoin blockchain for example, you could just say oh that blockchain is full I'll use another LN coin for the time being.
this doesn't sound right to me but i am not sure.
i say if you have funds in your LN channel then it doesn't matter if you use bitcoin or another altcoin and atomic swap it with bitcoin! you simply use the funds (bitcoins) that you already have in your LN channel.