A WiFi signal can improve a lot by changing to a channel that is not as overcrowded. You will likely need a prosumer WiFi device (e.g. Ubiquiti) or then something which supports OpenWRT. Consider also WiFi 6E -- if you carry your signal on a new spectrum then reception likely improves as well.
If cat cable is too thick, there's also the possibility to run SFP fiber instead.
If cat cable is too thick, there's also the possibility to run SFP fiber instead.