https://twitter.com/rabbitfordinner/status/1740609135044083919
this mf thinks we still have medieval walled cities, like dude, you can literally just... walk out of the city. I mean, yeah, you can indeed disrupt logistics, but there's a pretty big gap between "trucks can't get in to deliver supplies" and "entire population is trapped inside of the city". Also railway transport isn't real I guess
also love the idea of completely destroying supply routes into the city with... backhoes and gravel. I guess city folk don't have any construction equipment of their own to clear and repair their roads. Also I guess the roads are just going to be conveniently completely empty for however many hours it takes you to block them, because, uh...
do an area study 
The dude is kind of in the right. Most cities have a select few main "arteries" of trafic which people move in by - There'll be a few highways, some raillines and some rivers. A dedicated group could probably shut down most of those inlets, provided there's no one to stop them. You would still be able to drive to and fro the city though, just not in large convoys or in the direct passageway.
But like... Sieges were dificult in the middle ages, and cities haven't gotten smaller since then.