With mempool/electrs as backend you don't need txindex. But with romanz/electrs you do because electrs will only be used for address lookups.
Does the self hosted nostr:npub18d4r6wanxkyrdfjdrjqzj2ukua5cas669ew2g5w7lf4a8te7awzqey6lt3 really need -txindex when Electrs is configured? https://github.com/mempool/mempool/tree/master/backend
Discussion
I currently use romanz/electrs for Mempool, BTCPay and as my own private electrum server.
It would be nice if mempool could also use it for whatever it needs -txindex for.
Is the romanz/electrs index not suitable for some reason?