Do you think it is ok to modify or change wing chun and still call it wing chun?

Should the art be flexible enough to change with the times and / or geography as it moves to different places and faces different issues and styles than what it was designed to face originally?

Or perhaps it is a piece of history meant to be preserved as is. Even that is a difficult task as different lineages have added their own flavor in the recent past.

I'm curious at to how people feel about this. Perhaps a slight modification to the name would show the root but acknowledge that it has been changed. American Wing Chun for example or Wing Chun Jistu if you want to marry the 2 styles.

How do you feel about what is and isn't Wing Chun?