[...]
*I appreciate it has advantages for some altcoin users being able to see all their coins in one place.
Not even this..
You can only view the balances of the altcoins which are directly supported by ledger live (which can be sent / received via ledger live).
The majority of coins (especially those who only have 'basic' support) are not viewable / accessible using ledger live.
Only 23 out of 79 coins are natively supported and can be viewed by ledger live (excluding Monero, NEO, etc.. ).