Well, I disagree -- by "BF" you're definately only referring to 1942, BF:V, and BF2 because DEFENCE is a huge part of the titan mode. Corridors 1 & 2 of the titan are generally death traps for even an organized team if the defending team can get a couple of supports & medics down there (a recon sniper doesn't hurt, either...plus he can keep laying out APM's). I find myself spending at least half of the round defending in every titan game, and it's a blast.
There are more deployables in 2142 (sentry, support shield, squad leader assets, medic & ammo hubs, plus the APMs and C4 like you had in BF2). I have yet to have to deal with a "tank whore" or any vehicle whore for that matter...I can't think of anything in 2142 that doesn't have an exploitable weakness. Tanks & APCs are a breeze to take down if you aim at their rear, and the walkers are pretty weak in the legs and especially the undervents. Also, there isn't any arty in titan mode. I'm really trying to think about it...yeah...I can't think of any "whore" tactics in 2142. The gunships aren't ridiculesly strong in health, the transports can't be repaired from all passenger seats in flight & don't repair overly fast from the ones that can repair it, and everything's got an exploitable weakness. I guess the titan's guns can be a little unbalanced on Suez Canal because there are only 3 anti-aircraft turrets sparsely placed, but you can always take them out with a gunship or the engineer's anti-vehicle toys.
I know you all call it a mod, but once you seriously get to know 2142 better there are more diverse playing styles than BF2 offered -- and thankfully nothing seems to be overpowered / improperly balanced (at least not in titan mode...I haven't played conquest at all).