Yes this is a real problem. In the airline world it is go go go, until something forces you to stop. That force is either departure saying, uh I have no where to send them, so hold them, or a plane taking off and going holly * don't send anyone else that was bad.
The other way around is true too. Planes get in as quick as they can until they are forced to stop. Once on the ground everyone ttaxisin and if they were the last ones in they get to sit on the ramp because the ramp closes.
Here is the scenario. Tornado alley, busy airport, push time. Lets go with DFW. A storm is coming, like I mentioned, go go go until you are forced to stop. Outbounds all of a sudden start stacking at the end of the runway because they can't get out. 15 planes are now in line as this storm is 10 miles out. Inbounds landed, about 10 or 15 on the ground, but they can't get to the gate because the ramp is closed. All of a sudden the storm inintensifiesnd there is a tornado associated with it. 30 to 50 planes are stranded in the path of a tornado. That could be upup wardsf 1,000 people.
Now someone would think the airlines would logically not allow that. However, I personally have sat through 3 storms on the ground (with people and not at the gate) during one of these situations. Fortunately no storm was severe. One storm had small pea size hail. Just yesterday in recurrent a pilot told us how she landed in MEM and sat on the ramp because they entire airport including tower took shelter. A confirmed tornado touched down a mile south of the field. Imagine if that was a direct hit. The storm that rolled through STL (see video above). There were several planes on the ramp with passengers on board DURING THE TORNADO. The airlines are lucky all the tornado did was move the planes a few feet. The storm that went through DFW a few months ago. AA was in middle of a push and had numerous planes damaged due to hail. There are many videos from passengers phones riding it out in the airplane. Imagine what would have happened if the tornadic part of the storm went over the airport and not the hail core.
So yes, this is truetrulyerious issue. One day the timing will allialignre a strong tornado will make a direct impact on a large airport during a push. And unfortunately, right now there will be many planes just sitting there full.