I would say that it is pointless to research on eco-friendly transportation in this context if you don't take into account the reality of vulnerable citizens. How to provide sustainable mobility for women, elders and low-income people? I think that is the most pressing issue. So there is work to be done regarding how to fund the mobility system, especially considering the need for less crowded transportation in a pandemic scenario.
The best topic that come to my mind is: A Paradigm shift on transport business strategy, towards effective provision of transport infrastructure and facilities for efficient transport systems in developing countries.