For any non Americans, the largest interstates are one or two digits, divisible by 5. This particular collapse occurred in the Philadelphia metropolitan area.
This looks similar to what happened in Atlanta a few years back. In that one a bunch of trash stored under the bridge caught fire and caused it to collapse. Wreaked havoc on traffic for years.
There are a number of other highways that people can use as alternate routes to get around Philadelphia, but this could be a major disruption depending on how long it takes to repair the damage. I was planning on driving to New England sometime this summer, and I use some of those alternate route to avoid traffic... I'm guessing that won't be an option this year, though.
They had just finished that stretch as a rebuild in i think 2017. Used to live nearby and this stretch was under construction something close to a decade
A fire under a low bridge like that will weaken the steel structure and cause it to bend and break. It wouldn't matter if it was brand new or 50 years old.