So back when GameSpy was active if you tried to go online in SWBF1 on the PS2 it would prompt you to download a 1.2~MB patch. I don't know what that patch did, but I've had it on my memory card for years.
Is it required to play online with SWBFSpy?
AFAIK, to play SWBFSpy you only need to use this info
SWBFGamers - 18.104.22.168
Christian - 22.214.171.124
Depends. I think something has happened to the remainder of the DNAS servers cause ever since mid-2020 they stopped authenticating. You need AnthonyBF2's multiplayer patch in order to play online. Some people in certain regions are experiencing these issues but some aren't. For me, nothing authenticates.
The servers listed still authenticate for me on the release version of the game.