This is one of the typical cases where icculus actually was paid to port the server to Linux,
but decided to port the client as well in his spare time, free of charge. The client is labeled 'beta',
as it, IIRC, says in the README that it still has lots of issues.
The MoH client used the Miles Sound System, so he was required to remove it in favour for OpenAL
to avoid licencing issues. Maybe that's where some of the "unusual" problems are coming from,
assuming that he didn't what to invest too much time on the client.
So surely EA was not actively pushing for a Linux client in this case. It's more like EA didn't prevent Icculus
from porting and releasing one.