It's nowhere close to 5secs, that's a gross exageration from someone who probably pilots ESF a lot and never used a dual burster. It might take 5secs if there's 5 dual burster MAXes sure, but solo it takes way longer. I went and spawned a Mosquito with no upgrade and then shot at it with Dual Burster, side shots(assume like tanks side is more armor than back but less than front so it's good for average dmg value), 100%accuracy obviously. It takes 24seconds to blow up the ESF, 2magazines and a bit more(but it's burning so you could just let it explode anyway).
Now might be that it does less dmg on friendlies as I believe it used to take less than 2 magazines to blow one up but could be from random other people's dmg. Still you don't kill them in one magazine and each magazine takes 10secs to empty then reload. Even assuming you get full back hits, you'd still need at least more than 10secs to destroy an ESF, not factoring flak armor and more importantly not factoring the fact you can't have 100%accuracy unless the ESF is being a really dumbfuck and doing stationary bombing for 10secs while you're firing at him. Also unlike tanks, you can't flank ESF, getting back shots is purely random and mostly happen when the ESF flies away so you can't finish him.
Unless the ESF is flying direct trajectories, your accuracy goes down dramatically because of the travel time of flak. Literally all you have to do is zigzag and flak can't really hit you reliably because you have to compensate a lot when firing at an ESF so if he's not going the same direction for more than 2secs you're not hitting(maybe on the turns a few shots here and there). If you fly straight though it's fairly easy to land almost 100% accuracy(first few shots to adjust and then everything will land until the ESF turns).
Yes the render issues suck dicks and yes a bunch of AA MAXes will force any ESF to get the fuck out before they can even fire especially if they use a direct approach, but the whole 5secs kill? Pure bullshit. You will kill an AA MAX 1vs1 with stationary rocket spam before you even lose half your health.