The sound you describe is actually what happens when East Coast raised producers try to mimic that southern sound. Especially producers who learn how to produce from sampling. The bpm is what gives them away.

Like you said. Mustard is the sound of LA but he sounds nothing like Dre.
Dre himself was reacting to East Coast hip-hop when he started.

Drake deserves to be credited for giving this sound a home on his records.

Point of clarification: It's not just 808s that make the kids dance. After all there are 808s on Tribe's first album from 25 years ago. I think its CLEAN 808s that resonates with the youngings. Due to recording technology (12-bit samplers), 808 kicks sounds a bit dull in early rap when its played next to these 64-bit records. Its just a brighter and deeper sound now than back in the day.