This is really contingent upon what kind of private you're trying to do.
1) If you pretty much just want a model to enjoy/pleasure herself, conversation isn't really important.
2) If you have really specific desires, you should be able to communicate those fully and be able to clarify so she can give you the best show possible.
3) If the private is a chatty one (dirty talk / roleplay / even just plain old talking about life) then yeah, it could be a bit of an issue.
In any of these situations it can be helpful to tell the model that you're not great at talking back and forth. You can even use the excuse that your hands are otherwise occupied, if you prefer.
In any case, "bother" seems to be the key word here. I'd only be "bothered" by a lack of conversational skills if it caused the private to come to an untimely end.
(Really, unless I'm doing a "hey let's catch up and talk about our lives" private, I'm unsure how the "not knowing how to have a conversation" comes into play.)