I lived in Hollywood and Venice, both in the 60's. I had a car. Traffic wasn't so bad, is my recollection.
I grew up in the SF Valley (Granada Hills). Moved back to CA in 2008 and now live in south Redondo Beach.
LA traffic is fucking horrid now. It was bad enough in the 70s and 80s when I grew up. It's many times worse now. It's no longer rush "hour." All day is rush.
Now its a 2 hour ordeal to get downtown on the 110 or past west LA going north on the 405 ANY time of day between 5:30am and midnight.
My wife and I ski quite a bit and drive north to Mammoth or Tahoe or east to visit friends in AZ. We have to leave no later than 5 AM. Any later we add 1 hour to our drive time. Later than 6am we add 2 hours.
Inevitably we return in the afternoon on Saturdays from skiing or AZ. Hitting LA around 1-3pm. Going to Mammoth at 5am gets us there in 5 or so hours. Getting home takes 7+ hours because we hit Sat afternoon traffic.
And this will break your brain: Lancaster/Palmdale AND Santa Clarita/Newhall/Saugus are so built up part of the delay on Sat afternoon is caused by backups on the 14 through those towns.
But as soon as I hit LA it's stop and go on the 405 from the 101 interchange all the way to the Rosecrans exit.
One bright spot about where we live is it's 20-30 minutes north to LAX on PCH/Sepulveda avoiding the 405. So out of state trips are easy. We use a car service to drop us off and pick us up at the nightmare that is LAX.
Side story: During the first lock downs of the pandemic, LA was a ghost town. We'd drive up to the poppy fields of Antelope Valley or Angeles Crest or north county San Diego for day trips in under an hour. 85MPH the whole way and very few cars on the freeways midday. It was fucking surreal.