There is nothing stopping you from viewing all your coins with a Nano S (hell they even added ERC-20 token support 
)... If the coin is supported in Ledger Live, you do NOT need to have the coin app installed on the device to be able to view them. Once it is added to your portfolio, it'll show up just fine.
)... If the coin is supported in Ledger Live, you do NOT need to have the coin app installed on the device to be able to view them. Once it is added to your portfolio, it'll show up just fine.But you need to install the application once so the address/xpub can be added to the portfolio and the problem is most users are too lazy to install and uninstall the application few times.
I wouldn't regard Monero as worthless. It is the only coin which offers a decent anonymity. It is not natively supported by ledger live.
Additionally, there are very few wallet which support Monero, because Monero is very different (on technical level) than other cryptocurrency.