Good question. The problem with cooktops is that there is no standard size so if you need to replace the cooktop you'll have issues with your countertop unless you can get one the same size. Also, wall ovens tend to be expensive. With gas, a cooktop and wall oven(s) will generally cost more than a range. I don't know what induction pricing is these days. Also, you don't mention repair - particular if one part of the range fails. Repairing an appliance is still a viable option, depending on what the issue is.

Yeah it seems as if the mentality these days is just to junk stuff when it breaks when often the fix may not be as expensive as the consumer thinks. For computer boards it's usually worth ordering the part online and doing the repair yourself.

Induction ranges start at around $1500 and they can be found for less than that. For separate cooktop and wall ovens, it will be that much or more for each. Also keep in mind that induction ranges tend to come with pretty full featured ovens, but $1500 is a bare bones wall oven. If you want double oven, convection, probe, you are going to have to spend more. It's not hard to go over $3000 doing the component approach. There are ranges that cost that much too, but you won't be spending anywhere near that if you can give up the look of a slide-in model.

Bottom line: even before the days of induction the price difference between ranges and built-in components has been to high for people to worry about what would happen if one of the range components fails. You could repair the range or replace it entirely and still be money ahead compared to a cooktop and a wall oven. If you want the look of separate components, or it will affect kitchen workflow positively to have that layout, or if you want a high-end wall oven with features/performance not available in a range oven, go with the cooktop and wall oven. Otherwise, save your money and get the range.

Thank you weissman and hvteck - this was really helpful!