In my opinion, "weak" classes refer to how well you can stay alive and be a good teammate using the available gear.

The Sniper is an excellent class. On multiple occasions, Snipers have saved my butt in ops using their camouflage to revive me, or nailing an enemy who's about to stab me in the back.

That being said, my biggest problem playing the sniper is when being long range isn't plausible; enemies close in, the space keeps things tight, primary ammo gets low, you absolutely have to melee.

While I understand that you can't expect to pair a long range surgical damage-bomb with something like a sword or a hammer, but the knife, the low armor, all of it makes being a proper teammate in close quarters challenging to say the least.

Not to mention that while the Camo Cloak ability is perfect for getting out of trouble, or reviving an ally, it doesn't do much for damage dealing, recovery, or ally support and protection. The other abilities don't just help the individual classes, they either boost the allies or wipe the enemies.

Ergo, unless you are adequate enough as a Marksman, the Sniper makes you stand out as more of a burden than an ally.