@jensiii First of all, it's a mathematical phenomenon: 1 player out of 16 is less valuable than 1 out of 5 (let's say).
By tactical i mean, playing in a coordinated team. It's almost impossible, that 16 players coordinate each other in a good way. At 5 players it's very doable.
Right now, at 16 players per team your success depends a lot on luck: Wheather some guys of the other team cover one particular angle or your teammates move altogether in a clever way.
It's pretty much impossible to make a decision, based on all informations you gather, because there is so much going on (because of 32 players per game) and the lack of communication to every one of your 16 teammates.
Another problem, at least in Push and Skirmish, is, that you don't know how many enemies are alive or when they respawn:
So basically it's possible that you are unlucky and have to play against a full team of 16 players or if you are lucky there are just 2 or 3 players against you in that particular moment.
That's my issue with 32p matches. I'm missing the long term motivation, because it's almost impossible to play it perfect. A lot of times I feel like I've died, but could not have done anything better.
I believe that Firefight will be most effective played in Competitive 5v5.
Push and Skirmish will stay Casual due to the fact of higher player count.
Push could be done 5v5 as well, but it's not in the game right now. That might be an interesting idea.
Skirmish is too big for 5v5.