Here's what I see. Urban offices see employees file in between 6:30 and 9:00 each morning, with employees parking and then walking into their offices. The logistics of those same cars dropping off the riders without a large off street area to do so sounds like a mess.
Check it out:
Acme Corp has 200 employees. They're a new startup so they're murderous to their employees; they give them a bare 100sqft per employee. Acme Corp therefore occupies 20,000 square feet.
Nearly all municipalities require between 3 and 5 parking spots per thousand square feet, so Acme's office building needs between 60 and 100 parking spaces. If they're compact spots (8x16), that's a minimum of 7680 sqft (not to mention one parking spot for every three employees - Apple just built 11,000 parking spots for 14,000 employees). If they're full spots (10x20 in a parking garage), that's a maximum of 20,000 sqft.
Let's assume people show up at Acme between 6:30 and 9:00am. Let's further assume that everyone lives half an hour away and that there's no traveling salesman problem in the world that allows the car to not be empty half of the time. We can make one run between 6 and 6:30 then half an hour off. We make another run between 7 and 7:30 and then half an hour off. We make another run between 8 and 8:30 and half an hour off. Then we make another run between 9 and 9:30 and we're done.
Pretend Acme owns all those cars because capitalism. Let's assume a single rider at a time because capitalism and a lack of optimization. My 200 employees in 4 waves is 50 cars at a time. At the end of that wave all my cars tuck into parking spots in the lot. I've saved 10 spots just with that. In the meantime I've got an extra 1200 square feet for drop-off and pick-up. Let's instead assume I can make people ride 2-up - now I've got 35 spare spots. (and 4500 square feet for staging). 4-up? Holy shit. I'm saving more than 50 spots because I could do this whole thing with 12 cars and I could build a damn playground where people used to park. What if instead I replace them with 10pass vans? And remember - that's with 1 parking spot per 3 employees, which is dickish (most of them are going to spill onto the street).
We deal with this all the time in production - we've got to get a crew of 50 people into a bookstore and we're not allowed to use their lot. So we have everyone park in a lot a quarter mile away and we have pass vans that ferry them onto set. It takes like two. In our circumstance those cars are on someone else's lot but in an autonomous vehicle future they could park right where cars used to park all night and all day. If I can get four commutes out of a car instead of one, I need a quarter as many cars.
As far as bikes, I ride fifteen miles each way. More than, in fact. And I ride through some objectively sketchy shit. I'm here to tell ya - if there were ten times as many of me, there would not be people in beach chairs shooting heroin under the street lights. I opened a club once that got all the drugs out of Pioneer Square in Seattle simply by putting a bunch of dressed-to-the-nines twentysomethings in their faces every Thursday, Friday and Saturday night.