Cars, trucks, ships and trains are not worth it, unless they can run and be made in an environmentally friendly way, including ships at sea that regularly kill whales. If you're not killing bugs and birds and other animals when you travel, not to mention all the people who are killed and injured, it's because others have cleared the way. Or it's because you are travelling slowly.
Roads are also not worth it. They divide the environment into spaces that are too small for many animals to ensure their genetic diversity. Wildlife corridors do help some animals but not all and not nearly enough.
Even electric vehicles are not worth it, with all the damage done to the environment mining the raw materials to make them. Especially the batteries. Having electric vehicles travel in a tunnel and connected to an electric grid could help but will it be necessary?
The solution is for people to live near to where we work and grow our food and all the other raw materials we need for living, instead of having people commuting long distances to work and back everyday and instead of moving food and everything all over the world. Then we can cycle or walk to where we work or work from home. And we can bring the things we need on a simple hand-pulled trolley.
Even if sustainable cities are possible and large areas are set aside for nature in response to the climate emergency and mass extinction that's happening, how long will the nature parks be safe from humanity? Once the crisis is over we will be back to our destructive ways because only by living in nature will nature's well-being be foremost in everything we do.