If there's text or instructions in the gif, it's not on you to provide transcription services if you don't want to, or can't.
If it doesn't have instructions, then it isn't a gif recipe, it's just a gif of someone making something.
That's my take.
Now, is it nice for a poster to give the community something more? Sure. If you've tried the recipe and have opinions about it, or corrections, or whatever, it's definitely broly to add that in. It isn't necessary though, and afaik, it isn't a C/ rule, so it's all good