The only thing keeping tanks off the field is more tanks. The food chain is, Infantry > Blaster tank > Rail tank > Proto Rail tank.
Infantry can only go outside now because rail tanks are less effective against infantry, but they can still only be countered by other rail tanks. Go into a pub match and if no one has a rail tank a blaster tank can usually run free with minimal opposition. I went 43-0 in a soma that cost less than 60k ISK and I have 0 SP in vehicles.

Is it the high speed? That's part of it, some sort of webifier would make AV a bit more viable, but it still is an imbalance of cost and manpower to run a tank vs. manpower and cost to destroy a tank. If tanks could hack letters they would be the only thing on the field, has CCP even seen an ambush match since 1.8? Whoever spawns in enough rail tanks at the beginning usually wins.

I was optimistic about the new suits and equipment, but not changing the medium suit slots, over nerfing damage mods, not buffing AV, not changing the vehicle vs. infantry dynamic, and not adding any reasonable matchmaking makes me think that 1.8 is going to be one of the roughest builds to date, though not necessarily the worst.