Revert "Introduce a new "Old Image Formats" rule"

lib/metadata/policies.js

@@ -729,7 +729,7 @@ var policies = {
     "totalWeight": {
         "tool": "redownload",
         "label": "Total weight",
-        "message": "<p>The weight is of course very important if you want the page to load fast. Try to stay under 1.5MB.</p>",
+        "message": "<p>The weight is of course very important if you want the page to load fast. Try to stay under 1MB, which is already very long to download over a slow connection.</p>",
         "isOkThreshold": 1572864,
         "isBadThreshold": 3145728,
         "isAbnormalThreshold": 5242880,
@@ -746,16 +746,6 @@ var policies = {
         "hasOffenders": true,
         "unit": 'bytes'
     },
-    "oldImageFormats": {
-        "tool": "redownload",
-        "label": "Old image formats",
-        "message": "<p>Measures the number of bytes that could be saved by converting images to newer and more efficient formats. The best image format is generally AVIF and the second best is WebP.</p><p>Be careful, you need to provide fallback images for old browsers and search engine bots.</p>",
-        "isOkThreshold": 30720,
-        "isBadThreshold": 307200,
-        "isAbnormalThreshold": 512000,
-        "hasOffenders": true,
-        "unit": 'bytes'
-    },
     "imagesTooLarge": {
         "tool": "redownload",
         "label": "Oversized images",

lib/metadata/scoreProfileGeneric.json

@@ -5,7 +5,6 @@
             "policies": {
                 "totalWeight": 5,
                 "imageOptimization": 2,
-                "oldImageFormats": 2,
                 "imagesTooLarge": 1,
                 "compression": 2,
                 "fileMinification": 2