I agree that there are competing design goals. Privacy, speed, price.
XMR wins on privacy and price (less than BCH for txn fees) but still has a PoW block wait time (only 2 mins tho)
XRP wins on speed and price: <5 sec to confirm and essentially free to use ($0.000001/tx or somesuch) but is no more private than a Visa card or vanilla BCH
BCH is 2 hundredths of a penny. If something is cheaper nobody is going to care. Wallet generates speed. Like I say nothing is faster than the Bitcoin.com wallet. NOTHING.
Agreed that below a tenth of a penny almost nobody cares. But if you want to support HFT and price discovery in a real DEX to match wall street, $0.001 >> $0.000001
XMR mixes 11 randm UTXOs with each txn. That is also more combos than atoms in the universe. That alone is not enough to protect you. Are the input&output addresses & amount encrypted?