R7000 Latest Firmware V1.0.9.42_10.2.44 broke wifi

Always do a hard reset (paper clip thingy) after every firmware upgrade and manually enter all your settings. Your problems should be solved.

Backing up your current settings and loading them to your new firmware won't work and you will just have the same problems.

Actually, I recommend doing a hard reset every time you want to change any setting in your router. I know its tedious to reset and manually input your old settings and the new ones that you want to try out but that's the only way to maintain the performance of this router for longer periods of time.

If you finally notice any performance degredation over time, then it is again time to do a hard reset and manually enter again all of your settings even if you don't have plans to upgrade/downgrade your firmware. Always manually enter your settings through the web browser interface (not Genie app) and don't content yourself in loading just a backup. You will encounter problems with the performance of your router.