Uh, Litecoin is third with 16%, I didn't expect an altcoin dinosaur to still enjoy so much trust. I assume that due to the low fee, it is ideal for withdrawing assets from large exchanges, and then immediately converting them to BTC or XMR.
I often use LTC to pay for things when neither Lightning nor XMR is accepted by a merchant. Which is surprisingly common given that most merchants linked to fiat are scared of XMR and LN is a pain to setup.