It's a fair point about the dilly-dallying (although I believe there are rules like you can't be more than 3 min late, tho I don't know how strict they are.) I've definitely had rough lyft lines where I seem like I'm really being taken out of my way. But most of the time it's awesome, and kind of fun.
But the important difference that pavel was identifying was that you don't have to decide ahead of time that you are heading to the bus station. That's huge! You decide to head downtown or whereever, pull out the app, bam someone's coming to pick you up. To me this feels very different than, e.g., "casual carpool" in the Bay Area.
I think Uber Pool only gives you 1 minute from the time the driver arrives, but I've never had a driver leave without the second passenger when they took 5 or 10 minutes to show up. Plus people never like to admit that they're at fault; if they driver leaves after 5 minutes because a passenger wasn't at their pickup point, the passenger can probably leave nasty feedback and risk the driver being banned if it happens a few times.
I've had a pretty good experience with Lyft Line tbh.
The fare is based on the destination, so I don't get charged extra if the driver takes a longer route, or if the ride takes longer due to traffic, or if there aren't other passengers available to carpool.
The fare is also pretty reasonable - lyft line for 2 people comes out about the same as the Muni, so it's pretty much replaced Muni for me.
They also recently added the option of entering more than 1 destination, which is pretty handy when you're dropping someone off on the way home.
PS: I'm not affiliated with Lyft, just a satisfied customer.