I found that when managing my lightning node I need to keep sats aside in order to balance and generally manage liquidity on the channels. So I previously used the option of keeping sats in a lightning wallet that is not self custodial but as my node size is growing I no longer want a larger amount of sats on such a lightning wallet. I do share your preference for trustless BTC as preferrable but for a way to store some sats aside for use as reserve for node management I feel more comfortable using Liquid rather than a lightning wallet that offers, in my opinion, possibly a more limited degree of security in terms of trust.