I don't see the value in it at all. I'd rather just have a BBQ and a separate air fryer indoors.
An outdoor unit would kind of make sense if a kitchen isn't large enough for more gadgets, I suppose. Though I prefer dedicated devices that can be repaired or replaced independently of other things.
I sort of want one to do chips in, but it's way down on my list. First comes a stand mixer, a sous vide stick, probably a pressure cooker of some sort as I miss having one.
I'm not too interested in using one for more than chips. While belly crackling seems amazing in these things, I'm happy with getting almost as good crackle with some fire/smoke taste in the meat. Same with roasting other types of meat? I'm happy to be wrong but I haven't roasted meat in my oven for a decade now, so the convenience isn't a factor.