DC in Miami, explains why Telegram app is snappy fast for me. I notice similar speed improvement with Meta and other big tech apps when I'm on the west coast. I guess latency matters when your app is making tons of requests.
Most of big tech's major data centers are in Loudoun County, VA on the east coast not the west coast. It's centrally located to be great latency for the east coast and OK latency for west coast and Europe. Plus a friendly regulatory environment and lots of existing DCs (AWS us-east-1, Azure East US 1/2)
If you're feeling any better latency on the west coast it's more likely to be placebo than real.
On the contrary, Big tech famously has plenty of data centers on the west coast:
• Quincy, WA (Microsoft)
• The Dalles, Oregon (Google)
• Prineville, Oregon (Facebook, Apple)
• Hillsboro, Oregon (Cloudflare, others)
• Boardman, Oregon (AWS)