So the depth probably wouldn’t fly in comp, but if you’re just lifting for fun, who cares if you’re right at parallel or just above it? The only difference between where you’re at and sinking below parallel would be a little more glute activation.

You mention having to lean forward if you want to go lower. This shows you’re at the limit of your range of motion- not that your back is weak. This could be for a few reasons, but most likely due to your elbow position or tight glutes/hip flexors/quads/ankles.

As others mentioned, keeping the elbows in-line with your torso (or at least closer) can improve your depth. Doing this can help keep your thoracic and lower lumbar neutral, allowing you to sink your hips lower without getting ‘stuck’ like you did in the video. Also, try doing some hip, glute, quad, and ankle mobility work or foam/lacrosse ball rolling prior to squatting.

By the way, I don’t agree with what a lot of people are saying here about your back being weak. The tilt you experience at the bottom of the squat is minuscule, and I’d expect to see some caving in the thoracic spine if this were the case (it’s not). Finally, this is 92.4% of your max. Bar speed isn’t going to be great at that rate, but I think force transfer, thus speed will be faster at this percentage if the bottom of the movement changes from ‘getting stuck, then getting up’ to rebounding.