I have disabled the firewall before and still wouldn't work, not sure if there are any other issues. I have the 2020 Macbook air, also i've recently got a new router and thought that might do the trick but still no change just the same error message after a few minutes of entering the URL into the Heresphere web browser.
Viewing post in My Heresphere can’t connect to Quest 3—via SMB or XBVR.
If you can't load it in your phone's web browser, then the issue stems from your Mac/router/xbvr. You can try asking for help on the xbvr discord: https://discord.gg/wdCHXAG. Maybe some recent MacOS updates are preventing xbvr from communicating properly over your network.