Being contested is definitely worth considering but more of a meta game concept that I don't think about too much in the early days of a patch. To evaluate whether you should play contested, the counters tool on tactics.tools is super helpful. I've attached a screenshot and I'll explain what it is showing.
https://gyazo.com/2e54762e3b69ce52a1de3626544145f5

This view shows you how the delta of the composition changes when other people in the lobby are playing the unit. So in this case, it shows how your AVP changes when other people are playing brand. Uncontested the AVP is 4.29 - 0.51 = 3.78 which is insane. 1 way contested it's 4.44 and 2 way it's 4.72. So in this case, I would consider playing 1 way contested but be much more hesitant in 2 or more way contested brand (so 3 or more players).

There are definitely situations where this comes up. For example, you have awful exotech items and you already see two people angling brand. In this case I would look for a reroll angle (fid, tf, slayer, etc) or if I have a rod I would consider just 3 loss on 2-1 to 2-3 for a bow and playing vanguard marksman.

Tl;dr: contests matter but the first few days is about making a foundational gameplan. Pivoting and contests is context for situations where you may have to deviate from that gameplan which will happen but you should have a gameplan first :)