Looking for a word that describes thinking something is more common than it is?

I'm wondering if there's a good term for assuming knowledge, or other things, is more common due to my own experience.

Essentially it's like being out of touch with reality, but a little more specific.

One term comes to mind is confirmation bias, but again I don't think it quite matches.

Essentially it's because I've self selected to receive a certain amount of information, I assume it's common knowledge, only to find it isn't.

My personal example is, I repaired a broken kindle screen by replacing it with a new one, and opening up the old kindle.

I assumed a lot of people knew this was a possibility, turns out it they don't. I was surprised to realize this, until I concluded that because I work with technology it's in my sphere of knowledge.

Something about cultural knowledge? Frequency fallacy (I see it a lot, but that doesn't mean it's really frequent) -- Is frequency fallacy a real phrase?

I think it is   false-consensus effect:

In psychology, the false-consensus effect or false-consensus bias is a cognitive bias whereby a person tends to overestimate the extent to which their beliefs or opinions are typical of those of others.

There is a tendency for people to assume that their own opinions, beliefs, preferences, values, and habits are "normal" and that others also think the same way that they do. This cognitive bias tends to lead to the perception of a consensus that does not exist, a "false consensus".

This is the availability heuristic. Not a fallacy per se, but certainly a cognitive bias in our estimation of the frequency of events.

When faced with the difficult task of judging probability or frequency, people use a limited number of strategies, called heuristics, to simplify these judgements. One of these strategies, the availability heuristic, is the tendency to make a judgement about the frequency of an event based on how easy it is to recall similar instances.

So, since your personal experience includes events of disassembling electronic hardware much more frequently than the average person, your mind much more easily recalls instances of doing so — and so you over-estimate the frequency of those events in the general population.

Here's a very similar example taken straight from the Wikipedia article on the heuristic:

For example, if a student is asked whether her college had more students from Colorado or more from California, her answer would probably be based on the personal examples she is able to recall.