Swap files were required due to a bug/hardware limitation years ago where if you backgrounded too many tasks you would get cannot fork() errors that would essentially take out dnsmasq until you rebooted. Probably not necessary anymore but at the time a 2GB swap file would eliminate these errors on most models.
I can see this and other backwards support getting trimmed in the future as more models become EOL and the focus is on newer Wifi 6/7 platforms.
Invalid packet logging should also be fixed as of v7.5.5
Fix rule insertion for invalid packet logging @dave14305
github.com