Zakura rejected creating separate Zcash accounts for each transaction because Keystone hardware wallets sign only from account index 0 and Ledger devices require separate approvals for each account.

From the articleZakura Proposes One-Time Viewing Keys to Stop Quantum Linking of Zcash SwapsAlso in Zcash Builder Zakura Proposes Per-Swap Viewing Keys to Close a Quantum Privacy Gap - Unchained, Zcash developer proposes quantum privacy fix for NEAR Intents swaps