Who’s going to pass on these skills from one generation to the next?
I realise that you think philosophy is useless, but it’s essential if you are going to have something to pin your hat on. I mean heck, you can go with this whole survival of the fittest, but that’s not a great outcome for the individual farmer who has considerably more produce than he can reasonably defend.
If you want a working human society you need a philosophy of some sort to tie everyone together.
I mean the idiots who decided to get fluffy degrees and disdain honest work. I’m sure that new societies will form and that should be interesting to see. Farmers will be a priority for defense and villages will form, likely in the feudal form for some time.