Tri-rail is strictly a commuter train and is not an intercity train. Except for West Palm Beach all the train stations are just outside the main corridors of major cities, along I-95. You'll need to take a bus, shuttle, rideshare or taxi into the city center. Miami has it far worse as Tri-rail doesn't follow the I-95 corridor and heads west to Hialeah. Basically dropping you off into a train yard where you then have to take the metrorail into the city of Miami.
Brightline is another attempt at creating real intercity rail. A few stops at major cities. There is parking but it is not commuter park and ride.
Btw, I don't own a car. I use mass transit, rideshare, and care hire. In South Florida I'm a bit of an anomaly.
[1] Years ago, some friends and I took public transportation from Boca Raton to the Miami Zoo. One way took over three hours and involved several transfers between rail and bus systems.
My guess is they are banking on ridership to Orlando. It talks of connecting to Atlanta, and other cities, which would be nice. I've transplanted to Atlanta and would take a train over driving or flying (at a reasonable cost) in a heart beat.
Florida and California are the two hot spots right now that really need to succeed. I don't think I'll see real high speed rail expansion in the US before (if) I reach retirement age, but I think it will greatly benefit the next generation. But for that to happen, it needs a lot of support to expand now.