I just moved to LA (westwood) from Beijing last August. The traffic here is so light in LA compared to Beijing, and the air is really clean as well. In Beijing, it could take me a couple of hours to get home on 4th ring, 3rd ring was worse! And the traffic didn't disappear at 7PM, maybe 8 or 9.

Which direction? I live near you and regularly commute to the South Bay. It usually takes under half an hour to go 20 miles on 405. If you live and work on the wrong traffic pattern (ex. live in South Bay, commute north) then yes, you're going to have a bad time. If you move somewhere where your commute is against traffic then it's really not bad at all.

I drove SF to San Diego last year. Taking 710 from I-5 to CA-91 took well over an hour. Absolute insanity.

I think a half hour for 1 mile is definitely the exception not the rule. I could see it happening if there was a major accident blocking all of the lanes of the freeway but thats about it. For surface streets I think traffic dissipates much quicker unless you are talking about a specific choke point like crossing the 405 or getting on the freeway.

Can confirm. Would take me ~15 minutes to go from 405/Santa Monica to go get coffee in Brentwood at that Starbucks that's by all those italy like shops(it's been over a year and half since I moved so spacing on the street)