On balance, I believe that IoT will be worse for the environment. Appliances and machinery that today have life spans of 10-20 years will now be fitted with technology that becomes obsolete every 18 months.
While I advise my consulting clients to design IoT in a modular format (so that much of the technology can be swapped out without needing to replace the item itself), the fact is that, after several iterations of improvements, the underlying machinery will have to be upgraded. So, the end result is that components, many with toxic chemicals, will end up in land fills sooner.
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