Point of view
Minmatar commando m1 series
Approximately 800 hp
2 complex damage mods on wiki swarms

Not only can this fit not kill any basic armor tank, but the pilot either:
1 runs away, and I get + 75 (reasonable)
2 feathers the trigger and mows me down behind my cover
3 activates 2 hardeners, drives up to me, then mows me down or hops out and does it

Things that need to happen to fix this
1 large blasters should get instant dispersion on the first shot
2 if a pilot leaves their seat, all active modules, and passive reps deactivate, to reactivate on cooldownwhen the pilot returns
3 acceleration nerf. Driving around in the open should be as much of a death trap to tanks as it is to infantry.

Besides, it does not take 1.2 million ISK to make a fit with double hardeners and reps.

Best to ignore those two. And how they struggle making kills with a blaster now, I cannot understand. I kill people nearly at max range (150M), bursting my shots out.

Ignore the first two "tankers" that commented.

Yes, because our opinions don't matter. I've been in tanks for a year and a half, Taka has been in tanks since before Replication.

Likely what you ran into is a double hardened, double repped fit. Unless you can pump out the DPS to down it in like 5 seconds, you aren't going to down it. Meaning with just your main weapon alone, it won't die. Double repped with double hardeners is a bit OP atm and hopefully something that will get fixed.

Yet again, someone saying the answer is to nerf tanks. When are people going to get passed that and actually use teamwork all the time to down a tank? Do you really expect to solo someone that's been in PC in tanks? Best option you have is to set up a proxy mine trap, but that's too hard.

But in the meantime, perhaps a bit of advice. I personally don't use a swarm launcher, but I imagine it would work as well.

It works far too well for its ease of use.

What I have been doing is carrying proxies (remotes work well, just require some manual activation) laying down a trap to provide that initial burst damage.

Oh wow, you actually use your brain sometimes.

Tanks can be limited in movement,

Can be limited? Of course they're limited, they weigh 100 tons.

and flat areas (which a road provides) allow for the maximum movement potential, and a guide for when they have to back out. Watch the tank and note it's movement in and out of an objective, more than likely they will continue to use that same path.

Predictable people, yeah.

Once your trap is down, try to pull them in with hope of an easy kill. Positioning an LAV around a corner provides good bait, or just wait for them to move in. Generally though, I stick close to those proxies. Once that initial burst goes off, AV nades, generally the ones with best range, until you can throw no more and fire your weapon.

Yeah, YOLO homing AV grenades are so hard to use.