I’m sure of it. If you beat your son for smoking weed, I’m sure he would be his wife for burning the pot roast. A lot of fundamental Christian types do that a lot.
I actually doubt that.
Let's get our facts straight here, Jack bragged about 'only' two occasions in which he put his hands on Garrett, with his son supposedly initiating both confrontations, with Stroke Chokem alleging that the devil's lettuce abruptly caused mood swings. The choking incident in particular was apparantly brought on by Garrett attacking Tammy, and Jack admits that he lost his shit and lunged at his son in a fit of rage. Now, I'm not bringing this up to excuse or justify Jack's behavior, but rather that, while showing him being a terrible father, it's not exactly evidence that Jack was a habitual physical abuser.
Keeo in mind that Jack isn't actually a stern Christian paterfamilias. He's a weak hypocrite larping as one. He only adopted the Bible-thumping to get with his wife-to-be and then took it to the umpteenth level, like a shitty Walter Sobchak, but without actually practicing what he preaches. He's a gluttonous, spiteful scrounger who harps on about continence, love and work ethic. In everything we've seen him in, he acts like a petulant, entitled toddler with little self-awareness or regard for others.
One thing you can say for sure about Jack is that his delusional and selfish need to project a certain image harms the people around him. Him trying to be a traditionalist father fucked over Garrett and Jr. in the short term, and his Youtube career act involves wasting Tammy's time and money and alienating what few friends they had.
Going back to Garrett, it's one thing for family members to get into a physical altercation. Shit can happen. But it's another to act like a moralizing cunt and effectively disown them over it, severing ties indefinitely, only to brag about it years later because you think it'll please your fundie hosts, and you're that fucking desperate for validation that you'll go there.