OP said they did a factory reset and most of those features are not default. If those features were a problem, they'd affect wired also, but really those overheads shouldn't create a bottleneck at these rates.Things like QOS, Ai protection act as a bottle neck for speeds. Same goes for firewalls as well, to optimize a router it is useful to turn off all the features that aren’t needed as they act as bottle necks. In my experiences following those steps provided me with the best possible Wi-Fi speeds. But I do understand that changing these settings may be intimidating, that’s why I recommend saving a back up file before hand just in case things go wrong.
Once OP has a baseline for wireless LAN performance, and if there's definitely an issue outside of connected rates etc, which I'm not sure there is, then it's definitely worth looking at what _is_ configured.
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