Here’s a quick share of an article on how at-grade crossings are generally better and preferred over footbridges:

When Footbridges Cost Lives and At-Grade Crossings Save Them

The article effectively articulates the case for at-grade crossings and presents the facts and references in support of these crossings. I will only add here that context is still important along with an appreciation or understanding of the volume of traffic and occupancy of vehicles along the roads. Commonwealth Avenue, for example, requires footbridges but there should be better designs for these footbridges than the current ones along this highway. I think we lack good designs that we can refer to and this leads to a summary dismissal of footbridges where they are actually most suitable.

–