I do have two integral lamps, both bought by my wife, the hall light when it goes will change to bulb type, outside lamp will likely be scrapped the latter only cost £4 and to be frank it works better than a bulb as the LED's point down at the ground where I want to see not up in the air.
But down lights have never been about efficient lighting, they are more to look good, or bad depending on how you feel about them, I do have a group of 5 down lights
my wife thinks it looks good, well so do I it has grown on me, but there are 5 x 6 watt so 30 watt of lighting, and no more light than a pendent 12 watt bulb would give, I have another three sets of lights with GU10 bulbs, but these are on stalks so can be aimed at dark areas of the room, i.e. good reason to use them, they are not mainly decorative. Down lights are mainly decorative and do not light the room well when you add up the wattages unless you have a very high ceiling.
I have had a few bulbs fail and some smart bulbs have started a shimmer or turned into flasher units, but with a bayonet fitting easy to replace.
As to why they fail, I have looked inside the bulb,
and far to complex to work out what went wrong, however I have debated with my son, he is one on step ladders, about if surge protection devices (SPD) is really required, I have them, he doesn't and I have less bulb failures to him.
I can due to having solar panels view the voltage, frequency and consumption at moment 514 watt 246.8 volt and 50.1 Hz. I don't have a smart meter but would think they do the same, UK voltage should be 230, but it is permitted to be 207 to 253 if your supply is on the upper limit then can see lamps will fail quicker, never seen how a smart meter displays mine looks like this
plus all the bits about battery level and how much solar today which was poor. Why they say 230 volt I don't know, rarely below 240 volt.
I like the idea of the GX53 lamp, renewable bulbs, and larger than the MR16 emulated by most down lights, and surface mounted so no need for holes except for the wires in the ceiling, but not used them to date, the old fluorescent tube worked well in a kitchen but the 2D type looked better, but the modern day versions all seem to be integral. GU10 bulbs which can be directed where we want the light do seem to work well, they are out in the open so cool well, but sinking lamps into the ceiling as well as fire risk as you have holes in the plaster board filled with plastic, was OK when lamps were made of glass, and are mainly decorative, I have decorative light myself which are also used to light the room, but accept them for what they are, and if they fail well tough, just need to replace.