The FOB stuff they're talking about is grossly exaggerated. If you build it up moderately well, which only costs in-game money, invaders will fail far more often than not, especially if you have a bunch of supporters (almost assuredly random people) who are incentived to help defend your FOB because they get a ton of stuff out of it.
And the actual act of invading is the most intense and exciting thing in the entire game outside of a good Cloak and Dagger multiplayer game (which is infinitely more interesting than faux team deathmatch and the other one), and far more challenging than anything in the campaign.
LoktarOgar's comments