I mean... By definition isn't that a form of memory?

Whether it's learned or you were born with it doesn't really change that the information had to be stored and transferred which is...memory?

I guess what the OP means is that one definition of memory is that it is generated by your experiences. In this case the memory is the lack of experience (with a spider), because those genes keep you away from spiders. So it is possible that you can develop the RNA without seeing a spider, hence the opposite of memory.

In this case no information was "stored" after meeting a spider or getting bitten by it. Rather people who (by accident) had predisposition to avoid spiders happened to survive better.

Selection may be a part of it, but you may be wrong in saying no information was stored.

I remember hearing about this one really interesting experiment where they would expose mice to a specific scent (I think it was citrus), and then give them a shock. Obviously after a while, when the mice smelled that scent they would get nervous and try to hide (or something along those lines, this is from memory so forgive any erroneous details). They then bred those mice and separated the offspring from the parents so that there was no way they could learn about the smell from them.

When they exposed the offspring to the smell, they reacted in the same way their parents did. Without ever having been exposed to it before, or knowing about the shocks. Pretty interesting stuff.