To add to what others are saying, you should consider the framing of your question. Progress isn't all-or-nothing. There will still be situations where a truck, van, or car is the best tool for the job, and electrifying them will take time, or require advances in technology. We would still benefit from expanding public transportation and decreasing the need to use a personal vehicle for everyday tasks.

Eventually, though, yes, it would be good to replace diesel trucks with trains where possible, and electrify the ones we can't, when we can.