BCH's privacy problem could be fixed by everyone shuffling their coins all the time. It would not be a burden on the chain, as BCH can efficiently prune and enable some next-gen scaling like UTXO commitments, making storage of the whole chain all the time a thing of the past.

Monero doesn't scale, like, at all. Every node must keep 100% of the blockchain, all the time, forever. Especially with the recent full-chain membership proofs, any transaction from anywhere can be a member of the ring. As usage grows, Monero blockchain will grow out exponentially, and the need to constantly scan blocks for transactions will clog volunteer non-mining nodes.

I see only grim future and unfixable obstacles for XMR.