Tell that to AMC's "nto the Badlands" which was canceled as soon as it dipped into 1.2 million viewer territory in its third season.
That said no, AMC isn't going to cancel any "TWD Universe" series no matter how bad the ratings get because their programming department seems to love The Walking Dead IP and has invested so much money and has a multi-year marketing and release schedule that unless everything suddenly craters - yeah they'll just ride it out.
I wonder if cost is a factor too. World Beyond hads a way smaller cast (regulars and extras) and cheaper special effects and no martial arts coordination and sets that are just àbandoned places. Also this is PR for the Rick movie (s).
Oh and I saw a commercial of World Beyond that Talking Dead is a feature of AMC Plus... so I guess THAT is the main draw for their service... and why we don't see it or the usual commercials