I admit they look handy, especially for frozen veggies, but then I prefer my French Fries fried; we have a convection oven and I have used it twice.
I also have one of those ovens for reheating frozen burritos and similar stuff plus it has a two cup coffee maker. I have used it maybe six times in ten years (sad as it is better than the micro-wave and I can make a small amount of coffee with out a paper filter.
I gave the other half a new 300 some dollar Kitchen aid mixer because she wanted the apple peeler you can get for them - separately - last Christmas, has not been used yet, so an Air Fryer would just be another thing that get stored (we are OUT of storage space, when I had to totally clean out under a kitchen cupboard looking for some thing I did not find, I found kitchen gadgets that had not been used in 30 years and I had forgotten she bought.
Besides I like the taste of oil/grease on fried foods.