I have a lot of trouble characterizing tools as luxury goods. I don't consider my Dewalt tools "Luxury Goods" and they cost roughly twice what basic Harbor Freight tools cost.
You pay for longevity and performance. It's no different with phones/ tablets/ computers. If you want a phone or tablet that lasts 4+ years there is only one brand that offers that kind of device life.
Also, with Apple cranking out the base iPhone at $400, and the massive second hand market for iPhone, it's hard to argue many people associate the brand with luxury the way they do Coach or other luxury brands.
If anyone thought Apple was a "luxury" brand, the flop of the solid gold Apple Watch "Edition" sub-brand should have disabused them of the notion.
I still have my samsung after 5 years. I'm not sure why you'd consider it the only brand.
A smartphone is probably one of the most essential and important devices in many peoples lives these days. Certainly one of the most used. There is the option of Android instead of Apple, but as someone pointed out one time, iPhones are cheaper than flagship Android devices if you account for the support lifetime of an iPhone being a lot longer than any Android device. And that's not counting the cheaper iPhone Apple launched recently.
Likewise, for many people, a computer would probably be considered an essential device. Sure there are cheaper Windows laptops, but the cost of switching ecosystems is potentially quite high, and if you're already in the i-device camp you're probably going to stick with a Mac due to its integration with all the other things you have (and had before the pandemic)
I would count iPads as largely luxury devices.