re: Should I change my Roth IRA fund?

Hmmm you may need to check your info.
There are zero Vanguard funds that have a .02% expense ratio.

And there are only two of the admiral share class funds have a .04% expense ratio.
Also, admiral share class = a $10,000 minimum investment, so I wouldn’t think a young investor would be starting in an admiral share class anyways.

Most of the investor share class Vangurd funds have an expense ratio between .12% - .20%
There are a handful of admiral share class funds that are between .06% - .08% and that’s it.

The tgt date retirement funds for Vanguard are not expensive, they are on par with the rest of their funds.... still wouldn’t recommend them though. But they aren’t expensive for young investors or anyone for that matter.