I can only imagine in the US that if we could not use aircraft directly on the convoy, say they have very good air defense, we'd have dumped the bridges on the interstates in less than a day.
Edit: here's a link but this is not on the main highway. Unsure of the scale of this "operation" and if this was ordered from top brass or local initiative.
https://meduza.io/news/2023/06/24/v-lipetskoy-oblasti-gde-na...
It surely was considered. I can imagine in the state of panic even tactical nukes were considered, but sure, not reasonable.
But if Wagner forces would have actually pushed through, then they definitely would have blown up bridges, if the alternative would have been Moscow under siege or house to house fighting.