## Issue
After enabling Advanced Filter in Category Pages, the 'Content Type' filter only works for "repost/video/list".
## Root-cause
When `streamType` is not provided, it defaults to 'Video|Audio', making it always "defined":
```
streamType = SIMPLE_SITE ? [CS.FILE_VIDEO, CS.FILE_AUDIO] : undefined,
```
This seem to override the purpose of `defaultStreamType`, which will not be used unless the client explicitly set `streamType=null`, which currently is only being applied for `RECENT_FROM_FOLLOWING[]`.
```
const streamTypeParam =
streamType || (CS.FILE_TYPES.includes(contentTypeParam) && contentTypeParam) || defaultStreamType || null;
```
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