You need something in between to intercept the data and it just so happens that AAWireless works for that too while it's acting as a wireless bridge.
RustyHeater
I have the AAWireless dongle for my car and one of the advanced options is to "remove tap restriction" to allow over 6 taps in succession. Bonus, you can convert wired AA to wireless AA.
if you get/have AAWireless dongle you can set it to only connect when it also connects to the radio Bluetooth.
If not You can get a toggle switch USB cable to make disconnecting easier.
Have not tried, but Sonoff has a usb switch that you can control remotely and could potentially use Google Home. https://sonoff.tech/product/diy-smart-switches/micro/
Microsoft's Wolverine for the TCP stack was not available until Windows 3.11. An argument could be made that these systems are defacto air-gapped as they cannot communicate with modern networking.
The good news is anyone can grab the GrapheneOS PDF viewer. https://github.com/GrapheneOS/PdfViewer Or from the Google Play store https://play.google.com/store/apps/details?id=app.grapheneos.pdfviewer.play
I have that exact machine in my electronics "graveyard".
Peppermint OS was my GO-TO for speed and driver support out of the box. You can also stick in a 2GB SODIMM of ram. It will only recognize 1.5GB but still 50% more ram.
J1900 has no hardware switch. Every packet goes through CPU, so even LAN to LAN uses processing power. Add pfsense to the mix and it's probably choking.
TNG, The Drumhead. The social commentary aspect of Trek without being too heavy on needing to know the SciFi lore of the series.
Any plans to port to Android? The artwork looks great but I would suggest to invest some time to un-Zelda it so you don't get the Nintendo curb stomp.
Forza Horizon 4 Ultimate. Good deal for game and DLC bundle. Hoping it's a chill game with the open world.
Untitled Goose Game. Wanted since it came out and cheap enough not to pass it up.
Cult of the Lamb. Let's see what the fuss is about.
KIGHTFALL. So it's horses with go kart phstics. Only a couple bucks. I'm in.
The People Under the Stairs Army of Darkness Maximum Overdrive
All great campy flicks.