This comment is no longer needed, as the calculation is done in the 'grow' method (#58109)

lib/ansible/modules/system/filesystem.py

@@ -390,9 +390,7 @@ def main():
             module.fail_json(changed=False, msg="module does not support resizing %s filesystem yet." % fstype)
 
         out = filesystem.grow(dev)
-        # Sadly there is no easy way to determine if this has changed. For now, just say "true" and move on.
-        #  in the future, you would have to parse the output to determine this.
-        #  thankfully, these are safe operations if no change is made.
+
         module.exit_json(changed=True, msg=out)
     elif fs and not force:
         module.fail_json(msg="'%s' is already used as %s, use force=yes to overwrite" % (dev, fs), rc=rc, err=err)