because you don't care to give the customer longer term software support many consumers are not aware about the danger a unmaintained/non-updatable software st

because you don't care to give the customer longer term software support many consumers are not aware about the danger a unmaintained/non-updatable software stack introduces or that their (mainly) phone is unmaintained so phone vendor buys from B because A is often just not an option (not available for the hardware you need) and then dumps the problem subtle and mostly unnoticeable on the user there are some exceptions, e.g. Fairphone is committed to quite long term software support so they try to use vendor As or vendor Bs which have contractual long term commitment for driver maintaince but in the space of phones (and implicit IoT using phone parts) sadly sometimes (often) the only available option for the hardware you need is vendor B where any long term diver maintenance commitment contracts are just not affordable if you are not operating on a scale of a larger phone vendor E.g. as far as I remember Fairphone had to do some reserve engineering/patching to continue support for the FP3 until today (and well I think another 2 or so years), and I vaguely remember that they where somewhat lucky that some open source driver work for some parts was already ongoing and getting some support with some of the vendors. For the FP5 they manage to have a more close cooperation with Qualcomm allowing them to provide a 5 year extended warranty and target software support for 8 years (since release of phone). So without phone producer either being legally forced to have a certain amount of software support (e.g. 3 years after last first party selling) or at least be largely visible transparent about the amount of software support they do provide upfront and also inform their user when the software isn't supported anymore I don't expect to see any larger industry wide changes there. Through some countries are considering laws like that.