Simply holding a glute bridge for at least a minute for several rounds during a workout helped me start activating glutes that had been deadened from sitting at a desk job for two decades. I will often do up to 10 minutes of glute bridges in a 30 minute workout.

I usually combine glute bridge holds with upper body work using dumbbells (press, diamond press, skull crushers, flies) so I’m getting weight work in while activating my glutes.

Also mix things up with one legged glute bridges and glute reps (up and down with a weight on your hips). A key for activating your glutes during these holds is to make sure that you are pressing your heels into the ground, not your toes.

As you get those muscles used to firing during the holds, you should start to feel them activating more during squats, etc.

Squats are not the best exercise to target your glutes. Stiff-legged deadlifts, RDLs, barbell hip thrusts, glute drive machine, and glute kickback machine all target them much better.

If you want a glute-focused program, Bret Contreras is a widely respected, published doctor of sport science who specializes in glutes. He promotes the barbell hip thrust in particular for glute development.

I felt the same way and I changed my squat setup to start with my hips more under my body by putting the jhooks higher. I also focused on sitting back on the eccentric.

You can try the exercises shown in this video (timestamped) https://youtu.be/BOb3qUjg4s4?t=533

These are primarily for running but I believe it can help with your squats. All the best!

Front foot elevated Bulgarian Split Squats and Kickstand RDLs absolutely demolish my glutes.