The Gas Passer dilemma

The Gas Passer is a secondary for the Pyro that was added during the Jungle Inferno update and have an MvM-specific upgrade called Explosion on Ignite. The upgrade itself makes any robot covered in the Gas Passer's gas deal 350 damage to itself and robots around him when hit by any damage source. The upgrade itself cost 400$.To understand the toxicity coming from this, we need to look at Pyro before the Jungle Inferno update.Pyro was, and still is, an incredible damage dealer in MvM and one the best classes to deal with Tanks, being able to destroy them by itself on most if not all missions. Against robots, he is incredible at close range, but had to study bot aggro to flank them or outdamage them before he is killed and rely on Health on kill upgrades. Due to airblast (and any form of knockback in MvM overall) being a tool only used for extreme situations, or most of the time useless, Pyro players preferred to use the Phlog to maximize their damage output. Pyro is also the cheapest class in MvM to upgrade thanks to only needing damage and ammo upgrades on the Flamethrower, assuming the player using the class know how to use it optimally. Pyro could also help with money collection due to him fighting at close range most of the time.The main weaknesses of Pyro at the time were long range fighting, dealing with Uber Medics (like most classes), where all he can do is airblast them, and, debatably, ammo dependency.When the Gas Passer was added, it removed all the weaknesses Pyro had and damaged the position Demoman and Sniper had in the meta (the MvM meta, not the TC meta), since Pyro can now kill Uber Medics reliably (yes, even with the cooldown on the Gas Passer), using a non-expensive upgrade and with minimal skill required. When Demoman and Sniper are also considered powerful classes in MvM, and they can now be replaced easily by a 400$ upgrade, there is a balance problem. On top of that, Explosion on Ignite deals a massive amount of damage for low risks and with a low skill floor (and low skill ceiling).Some players did not like how the Gas Passer increased the Pyro's overall power and shaked the meta with low skill required. It got worse for them, as other, less MvM-invested players welcomed the change, thinking that having Pyro become stronger was a good thing, even saying that the Gas Passer made Pyro viable (when he already was more than viable). The power increase the Pyro got from this weapon is so great, that some players refuse to see a Pyro not using the Gas Passer.The clash of these two point of views causes a lot of drama in the MvM community, bringing toxicity with it. On one side, you have players that refuses to let Pyros use the Gas Passer, while on the other, any Pyro should be using the Gas Passer. Anyone in the crossfire simply cannot play Pyro without doing a gamble, as you might face an anti-Gas when you are using it, and a pro-Gas when you aren't.