You are of course right to say that, characterising conservatism as being focussed on the status quo, is a simplification. However this is often the case in discussing political ideologies, which are complex. However I wouldn't say it's inaccurate.
I think it is important to make the distinction between "conservatism" (a political theory) and "people on the right" (people). The former is an ideology which has a broadly agreed definition, the latter is a group of people in a given nation whose views and goals are changeable.
When you get into American politics, it gets even more complicated. The colloquial "liberal" in the US is very different from the actual political ideology of liberalism (at least as understood in academia).
This is true for other political terms, like socialism and conservatism.
So when an American says he is a liberal or a conservative, he often doesn't really mean this in terms of the textbook ideology, but may mean "I support the republican party" or "I support the democrat party", or "I am on the right of American politics" etc.
So whilst it is certainly accurate that (American) "conservatives" may not be focussed on retaining the status quo, conservativism (the ideology) is about just that. And yes, that's simplifying!