There's two reasons why I don't mind the the sciency stuff.

1. It's fun to connect it to the fantastic.

2. It sets guidelines.

The science doesn't have to be hard and fast because, yes, we can break the rules as gods. However, when fantasy connects to a relatable reality, sometimes it helps to bridge the gaps in terms of interpretation. Some people are leaning more heavily on science than others, but they are much closer to guidelines than rules. Don't feel discouraged by it, just do your own thing. If there's a clash, there will be GM discretion as the be-all-end-all arbitration.

ADDENDUM: When you have multiple authors and arbitrary mythological and unexplained parts of the universe that have no connection to how we understand our universe at all, it tends to make people feel copped out if something they could not have known to consider comes up. It's all well and good for the authors of ancient mythology, because they didn't have to play play-by-post RPs with each other. The guidelines keep it to an understandable scope for us, and if one of us wants to add something fantastical, everyone can get a clear sense of its impact.