I’ve read that during the war in Kosovo people there prized Dinty Moore beef stew above all else.
So it would seem to me that if you’ve got the storage space, just stock up on stuff like that. No need for expensive freeze-dried food unless you’re going off camping somewhere.
and who really wants to hunker down for 25 years?
The LSD church used to recommend 1 year’s worth but are now up to 2 years. Three months is a good start. Then you can go for a year and then two years etc. Store bought canned goods last indefinitely, especially if you avoid pull top cans.
If one has a few grand to blow, they can be stocked up quick with the LTS foods but you might want to try things before you stock up years worth. Would suck to open something after the shtf only to find you don’t like it.