Although I do not think it is important, is it plain suse or opensuse that you are using?
The following applies to any app that is built from chromium's source, not only opera.
After doing some research, I found out that it all boils down to this build flag in chromium's source
USE_SYSTEM_FFMPEG=true or false
Setting this flag to "false", which is the default value if ommited, will result in building the relevant libffmpeg library and use that for its multimedia needs. Setting it to "true" forces whatever is build from that source to use the system's libraries for its multimedia needs (the 3 libav* ones I mention in the other thread.)
As it seems, because this flag can only be either true or false, the resulting binary is either compatible with its own libffmpeg or the system's libav* libs, not both. Opera, being a closed source app, decided to follow the path that uses "false", ship its own libffmpeg and... you know the rest, I mention them in the other thread. If it was open source, I assume someone would have forked it and made it use the libav* libs. But it's not
As for the why it chose this path, I think it is obvious. Ubuntu (and its derivatives) users outnumber the users of any other distro, so they are keeping that majority happy with a working browser. You, me and the rest of us that are not on ubuntu are just a minority and building a different version of the same browser would be a waste of resources, time, money etc.(I think I said the same about dropping 32 bit support...)
Many other devs of closed source apps do the same, ignoring the same minorities, but that is how closed source works.
To sum up, if you dislike firefox and opera does not work on some sites, you can use chromium for those sites, provided that your distro packages it...