No lock down = nobody will go for the objectives...
There's certainly no proof of that in RO1 or the Mod, so why would it be true for RO2 all of a sudden?
Yes there will be times when some people don't go for objectives, but as noted already, the round will still end soon enough, those defending still can win, those attacking who suddenly decide to shift gears and attack can still win, and even if you can't get any caps because the defending team is pulling every stunt they have in defending and holding you back, if they sacrifice their reinforcements in doing so, the attackers can still win by simply wiping them out first.
In other words, the defending team could be holding all the objectives, but still suck at defending and quickly get wiped out.... thus all the objectives are automatically won due to no more resistance..... and vice versa.
With Lockdown on, it removes pretty much all of the above in almost all situations.
And how can someone say that lockdown prevents the game from being boring?
RO is never boring..... you're either still killing enemies or being killed yourself and you still have to use your brain.
Lockdown just restricts the diversity of the game imo.