The answer is not so clear. Model releases are contracts between a model and the photographer/videographer as to what the photographer/videographer can or cannot do with the photos/videos. Depending on the language stated in the model release, models can grant a broad range of rights, or they can narrowly define what the photographer/video can do with the photos/videos.
This is why models have to read every release they sign. And if necessary, have an attorney review the language of the model release to protect them.
So is it possible that your image will someday show up as an avatar somewhere? Quite possibly yes. But don’t they need to pay me for those uses of my image and likeness? Possibly no.
Again, an attorney should review the model release to see exactly what rights were granted to the photo/videographer. Just signing a model release now can mean that your career may be cut short at worst, or that you will be facing competing with your own image that can be digitally enhanced.
Imagine finding an account on one of the platforms that looks just like you but with perhaps different color hair, tattoos, body enhancements or different color eyes. All of that is relatively easy to change when digitally altering a photo or video.
If this happens to a model, there are some potential legal remedies. Beyond a claim that a producer, studio or fellow content creator breached the terms of the model release, a model could also bring claims for Invasion of Privacy and False Light, depending on the facts of the situation.
Perhaps, now is the time for content creators and models/performers to demand an industry standard model release that provides them the protection they need but also gives a studio enough rights to distribute the content without the possibility that the digital rights of the model or performer would be violated in the future.
This is a discussion that needs to happen on an industry-wide basis. Or at least, you should have your own model releases specifically drafted that you will only agree to sign. If a studio, producer or content creator refuses to agree to your release, you can simply decline to perform for them.