I worked on repairing Macs during that period and I suspect that no wifi card except this specific one would fit in the relevant slot of the machine.
They weren’t standard formats as far as I know and couldn’t be used across models because the shape of the actual card was never the same. It’s possible the connectors didn’t change though, or that a third party manufacturer made new cards specifically for that model, although that seems unlikely.
Another commenter (u/bloodfart) wrote that the connector was a standard mini pcie connector; I can’t confirm but that’s plausible and would mean it’s a lot more likely that an upgrade may be possible
One note of caution, it was really easy for an uninitiated repair person to sever the antenna wire from its connector when trying to disconnect or reconnect them, the cables are quite thin
We had to replace the entire screen assembly for that at the time but I’m sure it’s possible to do something less drastic if you are just working on your own machine