So what are the resource requirements for vanilla electrs? Hopefully not anything more than Bitcoin Core (minus all that storage and bandwidth).
The original electrs is meant to have kinda same requirements as the bitcoin node:
But the page doesn't tell much else than
I don't have exact specs (and I'm at work, so I can't check at the moment,) but electrs is pretty light to run. I have it running with mainnet, and as far as I can tell it's only using about 20GB of disk space and hardly ever makes a blip on ram. I'm sure it used more ram while synchronizing, but I don't recall it ever causing the machine to react slowly while doing other things. That particular mainnet node is a Dell SFF box with an I5 processor and 16GB of ram.
I also have electrs running on my testnet node (a RPi4 with 8GB of ram and a 128GB microSD card for storage,) and I believe it's using less than 3GB of space on that device. Electrs is obviously one of the lightest SPV servers out there, but it's been plenty reliable for me and my small circle of family and friends who've been using it.