From what I briefly remember, they aren’t jammers. They’re more akin to a DoS to the access point (I think it has something to do with spamming auth requests?) than jamming any physical signals.

They aren't jammers in the "blast out RF noise" sense, but since they are meant to disrupt legitimate communications, the FCC considers them jammers and has repeatedly fined companies that run deauth attacks to "encourage" people to use their paid networks: https://www.jdsupra.com/legalnews/fcc-issues-another-fine-fo...

I see, thanks for the clarification

As tgsovlerkhgsel said, they're not the classic style of jammer. That kind of thing is called a "smart jammer". And if you built that exact kind of functionality into a device and sold it (vs. just allowing the customer to code it themselves, like they could on any wifi device), you are probably committing a felony by manufacturing and selling a signal jammer.