Being new doesn't mean you can't try to do things. If the OP takes that perspective then they're just limiting their own potential.

Code is code, and can be changed. There's this weird inhibition in our industry to just trying things.

Senior or not, there's no harm in opening a PR. If there's a clear reason for not applying a change it's just a learning exercise. The PR can be closed without any negative impact.

Who knows, maybe discussing the PR will be teach the senior contributor something. I can't tell you how many times I've realized a prior constraint is no longer valid via a discussion o'er a PR. I end up informed, the new contributor ends up empowered and the code base lands in a better state -- win, win and win!

IMO these types of changes and the resulting discussions are healthy and absolutely crucial to the longevity of a successful piece of software.

Just opening a PR ? some time you have to step a way from a laser focus on JIRA and GitHub.

As a newbie at a FANG its going to take at least 9 months to a year to get that familiar with such a large code base.

And most of being a developer is not KLOC's or its modern eqvielent Fuature Points