> Safari outsources a lot to the operating system and as a result the interface and interaction becomes simpler, but less flexible.

Yes, definitely agree with that. But I think of "noise" as stuff that interrupts your normal interaction with web sites and in that regard I don't think Firefox is particularly noisy.

There are definitely a lot of features, settings and extensions with Firefox and while I don't use very many of them I do really appreciate the ones that I do use.