IMO, your expectations regarding the year and mileage seem too high for a standard Lyft ride. There is nothing dangerous or seriously old about a 2007 car. 100k miles is really not all that many. Professional drivers can easily drive 50k miles a year, expecting them to get a new car every two years is silly, especially given the low rates.

I'm not disagreeing with you about the suspension issue. That should be addressed, and I would agree that Lyft and Uber aren't really set up to address these issues well. I don't know enought about cars to say dangerous an old suspension is, versus the comfort factor.