Both are very cheap options, i.e. have lower transaction fees than BTC and USDT (maybe even ETH?), right?
Why is there no LTC, or BTH pairing for ADA? Needs development work that no one thought would be vital enough up until this point?
Ain’t it a question for exchanges?
Really don’t know. Is this something that would reside with them exclusively?
Yes. People can talk to them of course but it’s their business, their decision, which they’ll make on commercial grounds.