i am almost positive all of the views recited in this piece where still considered relevant today have since been made more accessible from textbooks to youtube videos
do you need to, or even need to want to, read this piece by russell? hardly, but at the same time it was written by a well respected individual in the field and there could be value in trying to dissect the text
regardless of your views on any single piece of writing i would wholeheartedly encourage your interest in mathematics
much like how i would encourage someone who dislikes or finds shakespeare too dense to still pursue a career in writing if they so desired but i would still recommend them to take another look
It is absolutely not a philosophy text. It's an attempt at defining a rigorous definition of the basic axioms we take for granted in mathematics in terms of pure logic, and then examining whether those basic rules of logic are themselves irreducible forms of nature or further creations of man. Essentially it seeks to support all higher mathematical thought by not just taking axioms for granted, but formally proving every one.
In my experience, logic falls into two catgeories: using math to study a formal system of logic; and determining "foundations for all math" and determining what is an "irreducible form of nature" and other such prosaic things (can the phrase "such that" be defined?). In my humble opinion, the former is mathematics and the latter philosophy.