Parking is only really a problem below 59th st or so. You can usually get street parking by driving in circles for 20 minutes, or go to a parking garage and pay ~$8/hr to park.
But outside of rush hours and especially a few places like the tunnel approaches it's not a big deal. People do it constantly, it's totally normal for people from NJ or Westchester or LI to drive in for dinner and park, that kind of thing.
The random chance of winding up in standstill gridlock is just way too high. I can’t even count all of the times it has taken me over an hour to go like five blocks. Every time I’ve had the bad idea drive to the office to get a head start on an after-work trip, my mind is blown that some people actually do it every day, by choice.
I imagine all the congestion toll will do is swap the cost of congestion from time to something more palatable like money. And a windfall for people that own real estate just outside of the tolled boundary (yay brooklyn)
(I mean, there are also more traditional parking garages, both above- and below-ground, but the premium on real estate is high enough to justify more expensive solutions to maximize land value also).
Driving in Manhattan is actually pretty pleasant, all things considered. Wouldn't even make a top 10 list for me of worst places to drive in the US. I think in part because there's a weird selection bias where people think it will be bad, so bad drivers don't even attempt, and you're left with a cohort that, on average, has above-average driving skills.
Seattle on the other hand? Worst driver's in the US by a country mile.