Mini 2 iPad Mini suitability? I get this message:

I would like to use a larger tablet than my iPhone SE 2020 with my Mavic Mini 2, which works fine, but provides a smaller image than I would like. When I use my iPad Mini 5th generation, I get a message: “Mobile device CPU fully loaded. Related performance will be affected.” And it seems that sometimes the image is sometimes pixelated, or blurry, or lags a bit. Does anybody know what that message means, and if there is a iPad Mini that would work flawlessly. The next generation would be the recently released 6th generation.
Or is there any way to improve utility of the 5th generation? It is a Wifi only, and used out of range of any wifi.