I was investigating on my sound issue with localized voices and noticed the cache was not purged after FAF updates.
So many FAF obsolete versions are remaining stored there for nothing.
Take a look at AppData\Local\Gas Powered Games\Supreme Commander Forged Alliance\cache
BTW :
I'm wondering how to run FA with the /purgecache command line switch through FAF.
This is probably intentional, as you need the old versions to watch older replays
So once a player watches an older replay, the client keeps that version around in case the player wants to watch another one of those replays
That cache is a game cache and not a FAF client cache.
If you want to apply the command switch you can append it in Settings -> Forged Alliance Forever -> Command Line Format for Executable
Put it behind the %s
(Mine might look different because I'm running on Linux)
"Nerds have a really complicated relationship with change: Change is awesome when WE'RE the ones doing it. As soon as change is coming from outside of us it becomes untrustworthy and it threatens what we think of is the familiar."
– Benno Rice