This problem won’t be as bad if and when support for Content Credentials becomes widespread, since you can just decide not to trust images without them, sort of like not trusting a website without HTTPS. Since anyone can add their own Content Credentials to an image, a warning is displayed similar to a certificate warning in your browser that the Content Credentials come from an untrusted entity. I think with more awareness about Content Credentials, platforms will feel more pressure to support them, so if you want to see this feature on your favorite platform, speak up and gather support.