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I have the sparrow wallet installed on my MAC OS, and the node (rpi Umbrel) has bitcoin core installed on the Umbrel software. The Node and Mac OS is on the same LAN but of course separate machines.
OK... so it's an rPi with bitcoind running.
I assume your electrum node (electrs) is also included in this "umbrel" system, so it's also installed on your rpi.
So, basically, the traffic between bitcoind and electrs isn't an issue... It's all on the same host.
Since you tell us electrs is only listening on port 50001, it isn't using ssl and it is listening on a port other than 127.0.0.1.
When you're on the same lan, i wouldn't say this is a big issue... Somebody that has access to your LAN could potentially capture packages between your laptop and your rpi, but those packages do NOT include data that could be used to steal from you! somebody on your home lan could potentially learn which addresses belong to you, but that's about it. Really, you have bigger problems if somebody with the capability to capture and understand traffic between your laptop and your rpi has access to your home LAN.
Just make sure you're not forewarding ports from the WAN side to port 50001 on your rpi!
When i was talking about a reverse proxy (nginx for example), i basically mean installing a daemon on the same rpi that's running electrs. This daemon is listening on 50002 using tls and "forewarding" those packages to port 50001 on localhost without tls. It's actually pretty easy to do this setup... i have it somewhere in my historical posts if you're interested... But i have no idear if "umbrel" will make it easy for you to install nginx (i have never used umbrel), if not you'll need a tiny bit of technical background to get things up and running.
If the above it TL;DR;, here's the short version:
sparrow wallet is managing your private keys, these keys do not leave this wallet. Make sure your macOS is secured, your sparrow wallet is genuine, make sure you pick a strong random password, make sure you don't save a backup of your wallet somewhere vulnerable.
Bitcoind is the only daemon talking to the "outside world", as long as bitcoind is using Tor, you have privacy. All other traffic is on your LAN. Sure it would be nice if it had TLS, but if it doesn't, i wouldn't worry to much. Sure, a hacker (or a family member) could learn which addresses you own, but your funds will be safe as long as your macOS is safe, your sparrow wallet is genuine, you pick a strong random password, you don't save a backup of your wallet somewhere vulnerable.