Is there any intention to update it? especially if the service is misused as a mixer?
No need to change anything.
This is clearly not a mixer, and you can't send bitcoin to get mixed bitcoin, or send ethereum for mixed ethereum.
I know that the eXch representative has said no to including the TRC-20 version of USDT on the platform, but I am still hoping that will happen. Out of all the USDT variants, I use that one the most. DAI is, obviously, the best if you have to engage with a stablecoin, but I haven't met many people that want it as much as they want USDT as long as they have a choice.
This is one of the worst crap stable coin blockchains, and fees are often higher than on all other alternatives, unless you stake trx shitcoin.
It would be much better to see L-BTC and L-USDT on liquid chain, and admin already confirmed they are working on it.
Here is comparison:
https://gasfeesnow.com/https://liquid.network/