Those pouches are of limited value. They may attenuate a bit but they do not fully block the RF that goes back and forth. To really block the RF involved with these fobs, one needs a metal box. Steel works better than aluminum, although thick aluminum works fine. I would not trust aluminum foil. Again, it may attenuate but not fully block.
When the day comes that I might happen to have a vehicle with a proximity RF fob, I will either use a small steel amo box to store them. Or a small cast aluminum box [Hammond makes great ones] combined with a strong spring clamp. Likely one for the house and one for the office. While in your pocket a pouch is better than nothing. Some pouches might be better than others.
Its all about RF shielding. Lead is best but not practical, steel is better than aluminum of equal gauge, aluminum is great if thick enough.
Now folks, keep in mind that the old fashioned remote entry key fobs 2019 and earlier Frontiers transmit in one direction. You press a button, it unlocks the doors, press another it locks them. Your fob has a transmitter than sends a signal to do this to a receiver in your truck.
The new type are different. It sits in your pocket and you can just push the button to start - 2020 forward Frontiers. The fob transmits to the truck, the truck transmits back to the fob. This is the kind that one needs to be careful of with high tech thieves.
Disclosure - I
love steel amo boxes. I'm not a gun guy [but no disrespect to
responsible gun owners], but I use large amo boxes in my truck bed for storage and I use then as electronic project boxes. Now, I suppose the ultimate "murse" or man-purse would be to carry around an amo box for my keys, wallet, etc. I'm not that wacky, well not yet. Would make for a funny skit though. Might suggests it to my wife for her improv troop.
Oh, and plastic jerry cans make decent speaker enclosures if you stick enough acoustic wadding in them