After plenty of thought, I believe I have devised a better system for basing lamps. Obviously it is way too late to change at this point, but this is how I wish it would have been done in the first place. Here we go:

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Unballasted/Mains voltage lamps:
- All have bayonet-style caps (we can all admit they are better than Edison screw)
- Different pin quantity/position corresponding to lamp voltage (different voltage lamps won't be physically compatible)
Bayonet sockets are a little safer than Edison screw sockets, and they are also a lot easier/quicker to use. This is just better for general purpose applications. There are also smaller versions of bayonet sockets that can replace the sort of "candelabra" E12 or E14 style caps.

Ballasted/HID/LPS lamps:
- All have Edison screw bases (E17 for things like G4S11/GTL3 ballasted lamps, E26 and E40 for larger lamps)
- Keep modern system, still no way of preventing different lamps from being interchanged illegitimately
Edison screw sockets are more robust and just generally more suited for more industrial lighting styles. They do take longer to use and are slightly more dangerous, but this is nothing new for industrial lighting.

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Again it is way too late to change now, but it does bug me a little that so many things can go wrong with a system that has been around so long. This doesn't address the fluorescent tube issue (a whole other can of worms), but whatever

There is one significant problem to having that many variations of essentially the same base: Instead of one part number, you need to manage about 10 of them.
That would make the servicing logistic a nightmare.
Plus the same will be valid for tooling in the lamp production line. In fact just that alone would bump up the lamp lroduction cost easily by 10's percent, way above the normal profit margin on these products.

So in reality the development activity went exactly the opposite direction: Looking on what else could be kept exactly the same for more product types (lamp wattages, life ratings,...). So how to make much more than just the base the same for as much lamps as possible: Bulb shape and size, stem assemblies, even gas fill pressures and composition, fuses. Even when it means for some of them it won't be exactly the optimum for that given exact product.

B22 has some problems with corrosion :

 - The pin springs are not very strong, and if the contacts are a little corroded, they dont always provide sufficient wiping force to break the surface and make a good connection. In E27 the center contact is normally more rigid, so is scratched with more force when the lamp is screwed in. The side contact gets way more wiping as the lamp is screwed past it. So E27 can take somewhat more corrosion before it fails

 - When you already installed the lamp in a socket with corroded contacts, E27 will stay where you left it. B22 still allows some movement of the lamp, so it fairly easily loses the good contact spot

An ignitor will likely break the oxide, and SOX lamps are normally used by professional users, which makes B22 an ok choice for SOX. But not so much for home user (straight 120/230V) especially in wet locations

Having used both ES and now B22 (as i recently acquired some long festoon with B22's, ask me how i know about the corrosion problems....), and even before B15 in various configurations (all signal lamps in the car....) i would say that for general use ES is more convenient as it needs less precision. Just stick it approximately there and screw

This would especially make a difference if you already climbed into some inconvenient or unsafe position to reach the lamp and can barely reach it

So there goes your "we can all admit" no, not all



Consider GU10 for "home user" lamps for dry location. It is a widely enough adopted standard so not at risk of becoming obsolete, it is made of ceramic materials so is good for both "hot" and "energy efficient" lamp types, and safe from poking in fingers

It will however have the same problems as B22 when it comes to corrosion, and even worse because the contacts are not accessible for a quick scrub with a screwdriver, so you really will have to replace the socket if it fails

And if made of ceramic (for "hot" lamps), it is more expensive than both E27 and B22 to manufacture (both in terms of $, and resources that will be discarded when the lamp EOLs). For compact lamps there is no choice, but for plain old Incandescents it may be possible to simplify it by reducing the ceramic to just an insulating disc, and making all the rest out of a metal cap, or making the entire base out of a low grade die cast glass



If you used B22 for HID lamps (as much as possible before ignitor voltages become a problem) you could key it differently for different ballast requirements

This have indeed been done in England for Mercury lamps, tho i think they all used the same 3 pin configuration

However, this would result in complicating retrofitting of lanterns (such as from Mercury to SON, or from HID of any type to CFLs and LEDs), which would result in way more good lanterns getting replaced and trashed

Also, there is an historical reason why HID lamps use the same base as incandescents : In the beginning of HID, they were used to retrofit incandescents in existing luminaires (by dding a ballast in series with the existing wiring. It was all Mercury back then, so really just a series choke). As HID was introduced, it got already intrduced with the existing caps, so it was already too late to change - Until many years later, when new types of HID lamps were developed that actually justified introduction of new bases like G12