Yea, Connection count is the same either way.
I don't have any "Smart" devices so haven't looked in detail at how some of them work, but with the world still stuck on IPv4 then yes being stuck connected to a central sever (like most messaging apps work) is probably the best way.
IPv6 will and should change that. The Central server will probably stay even after migration, but your devices would probably be allowed direct communication instead of passing through a proxy. Some "connected" devices are not connected through central severs for their main task, so in a way both of you are correct. But those not using a central type of server might not be contactable.
I will go back to what I said earlier, chicken and egg. Will the design work or be a problem in the future, we wont know until we try. But I know waiting until the last moment to do something rarely works well (Look at UK politics at the moment!).
The Game Consoles, VoIP, and VPN/Remote file access are really three of the most simple things that NAT gets the way of, to me just those three things are enough to say we need IPv6 now. There's other benefits to IPv6 that we don't even touch on that much. Basically it's time to start, not time to keep thinking about it.
I guess the only upshot of VM taking so long, is that by the time they finally get ready to deploy DS-Lite, the world will have moved to IPv6 and they can just shelve the whole thing.
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I do not work for VM, but I would. It is just a Job.
Most things I say I make up and sometimes it's useful, don't be mean if it's wrong.
I would also make websites for them, because the job never seems to require the website to work.