I think the closest type of attack to what you're referencing would be a WiFi deauth attack. There are ways to protect against it, but ultimately I think trying to secure WiFi against dos is like trying to secure a glass door against break-ins by putting more locks on it. WiFi operates on unlicensed spectrum, so no license is required to transmit. The tradeoff you have to accept when you use unlicensed spectrum is that everyone else can transmit on it too, so there are no guarantees on the quality of that spectrum. You can put in all the technical defenses you want but it will have a hard time stopping someone who just comes along and spews noise on the spectrum.
-- btw, i know that a jammer could always be used in such a distance, but i am avoiding worrying about high skill attacks, since they are
illegal, and an amateur would have a hard time trying to produce one.
Laws will of course vary depending on jurisdiction, but making WiFi unusable through a deauth attack could also be considered a form of jamming and potentially also illegal, so I'm not convinced that someone willing to perform a deauth attack would be unwilling to perform RF jamming. Additionally, a lot of WiFi interference happens unintentionally. Microwave ovens are infamous for wreaking havoc on 2.4Ghz spectrum. Cordless phones, wireless security cameras, baby monitors, and neighboring WiFi networks can all cause interference, sometimes to the point of making WiFi unusable. These forms of interference would generally not be considered illegal jamming, since it's unintentional.
Another interesting tidbit about how WiFi works is that as a form of congestion control, if a WiFi device hears another WiFi device transmitting on the same channel, it must wait for the other device to stop before it can transmit - even if the other device is associated with a completely different network. So even the existence of another network on the same channel as yours, if transmitting data constantly, can severely degrade the performance of your network.
In conclusion, if guaranteed network availability is important to you, wired connections are the way to go. WiFi should be for convenience only.