I realize you posted this in the incan flashlights subforum, but it applies to bulbs in general as do things others already wrote which I agree with, especially CRI. As far as flashlights, I have plenty of rechargeable batteries and haven't gotten around to modding all of my incan flashlights to LED (have done some, enough to get by, but some are not really worth the bother), so I might as well have some batteries in the incan lights I have, scattered around various places in addition to the LED flashlights I'd always grab if one is closer... like in my pocket.
As far as home/other building lighting, incan can go in lamps and housings you like too much to get rid of, that have sealed chambers and would get too hot for LED to have good life.
Incan heat is good outdoors in winter to melt off ice and snow, or in very hot climates. It's not that LED can't do hot climates but it's going to be a custom design with (otherwise) overkill heatsinking and more robust driver.
Incan is more power surge resistant.
Incan works well with existing old dimmer switches, where an incan bulb running at a small fraction of its full brightness will have a very long life and not consume as much power.
Incan is very old, mature tech so you usually get the lifespan you expect out of them. I've had about a half dozen major brand LED bulbs fail within about a year. They were GE BR30, but I've read similar reports of other bulb shapes and brands, that aren't achieving even 1/10th of their estimated running hours. I suppose there is consolation in that they did run long enough to make the energy saved, pay for their higher cost than an incan bulb, especially in the case of BR30 incandescent which are often pricey due to deposited silver for their reflector.
Heating. If the cost per BTU is similar from electrity as from gas, incan are useful for adding a little heat to rooms you're occupying (which is why the light is on), but of course that is a detriment in hot summer climates.
Nature's insect traps. Incan bulbs attract far more flying insects. More flying insects mean spiders build webs there, reducing nuisance insects like flies, moths, and mosquitoes.
Last but not least, darning socks! The round glass globe of an incan bulb is great to stuff in a sock, without the needle getting stuck in it like it would with a plastic globe while you sew the hole shut. Granted today everything is considered throwaway so you just buy new socks, but it is still less expensive and more sustainable to put 2 cents worth of thread into a repair instead of paying $x for a new pair of socks, and the same strategy can keep other clothing usable when you need something to wear doing rough or dirty work.
Incan is more recyclable and uses materials we have in abundance, are mostly silica and aluminum which are #2 and #3 of the most abundant elements in earth's crust.
Don't get me wrong, I like the power savings and heat reduction of LED, especially the power savings for portable applications. The only reason I would buy an incan flashlight today is if I were planning to mod it to LED, and in that case some older incan lights have a larger area in the head which makes them more moddable by putting a larger heatsink in, for example I can get 5W of LED light with a passive heatsink in an old Ryobi P704 flashlight (that takes a tool 18V Li-Ion battery) while their ready made modern LED equivalent P705 is only ~1.5W.