No they dont. There is a structural limit to that airframe like all objects and a load they can take. Otherwise you can try to hang 4 Ton bombs off their wings and see how they crack.Don't the F-7s have a robust air frame?.
The Mig-21Bis versions you have shown all specifically had modifications to strengthen the airframe. The F-7 is based off the first generation Mig-21C and hence does not have any of those improvements.
It is also the reason why the Chinese and their attempt at the F-7FS still only managed a point defence fighter because they were still working off the first gen mig-21.