[ie/youtube] Require PO Token for iOS HLS formats

yt_dlp/extractor/youtube/_base.py

@@ -260,9 +260,8 @@ INNERTUBE_CLIENTS = {
                 not_required_with_player_token=True,
             ),
             # HLS Livestreams require POT 30 seconds in
-            # TODO: Rolling out
             StreamingProtocol.HLS: GvsPoTokenPolicy(
-                required=False,
+                required=True,
                 recommended=True,
                 not_required_with_player_token=True,
             ),

yt_dlp/extractor/youtube/_video.py

@@ -256,7 +256,7 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
         '401': {'ext': 'mp4', 'height': 2160, 'format_note': 'DASH video', 'vcodec': 'av01.0.12M.08'},
     }
     _SUBTITLE_FORMATS = ('json3', 'srv1', 'srv2', 'srv3', 'ttml', 'srt', 'vtt')
-    _DEFAULT_CLIENTS = ('tv', 'ios', 'web')
+    _DEFAULT_CLIENTS = ('tv', 'web')
     _DEFAULT_AUTHED_CLIENTS = ('tv', 'web')
     # Premium does not require POT (except for subtitles)
     _DEFAULT_PREMIUM_CLIENTS = ('tv', 'web')