I'm confused why it's called a "wiki" though, I didn't see how to contribute? Was that just a funsies name? Wiki to me means something that's editable by the community.
I'm also not quite sure the audience here, because it seems to indicate "find exercise by muscle group" to be the way to use the site, but that's not really... useful... to people that don't know proper form for some of these basic exercises. If I view the site like this: https://musclewiki.com/directory then it makes sense, like, ok, I set up a training regime for myself, or I'm looking at the one set up for me by my trainer, and I forgot cues and good form for a given exercise, lemme just look it up real quick in this really light weight, functional website. Boom, GIF, cues as bullet points, done. That is a great use case.
What I'm worried about is a noob will come here, hit "biceps," then have a workout day of five kinds of curls. Which I guess to many is obvious why this is bad but just in case: broad strokes, if you're lifting, especially as a noob, it's better for your health, strength, and long term safety to be doing workouts that work your entire system, rather than "targeted" exercises only, such as curls. A good noob exercise plan is some combination of barbell squats, deadlifts, bench press, rows, and overhead press, or for bodyweight, pushups, dips, pullups, and squats.