I'm not the one down-voting you. I see your points and they are valid I just don't necessarily agree with them.

1. Yes they do, unfortunately said "marrying" of them to their own management platforms makes them un-necessarily difficult to work with. This is fine when you have an army of network engineers or you have bought into their entire proprietary system (still usually needs army of network engineers) but it's a pain otherwise. There are plenty of other viable Broadcom Trident based gear etc out there that is used at huge scale (see Quanta) that if you use aftermarket firmware actually works really well. Bing was built using vanilla Quanta gear, I am not sure about Azure but I would assume similar.

2. I think you are misconstruing my words. I wrote my own platform for my purposes. It scales well enough for what I do and that is great. I am not GOOG and am not pretending to be, at their scale all problems become immensely more complicated. They do however have immensely more resources to throw at said problem. The revealing point however is they actually went that path though. I am sure if buying a bunch of vendor gear and going with MPLS would have fixed their problem then that is what they would have done.

3. Mesos and Kubernetes are just 2 implementations of a much more wide spread cluster job scheduling idea that has been around for a very very long time. The specific examples mean very little, the point is more that they change the paradigm in which you operate your datacenter. You no longer think about specific hardware and networks being assigned to specific departments or projects, instead everything is scheduled on one pool of resources and SLAs etc are all built into the control plane. Once you have this for compute it follows the same will be done for networking using the same datamodel and infrastructure. My point here is this is why GOOG, AMZN and MSFT either build their own gear or go the more open route, you can't do this unless you are able to hook into your network plane at a low enough level.

4. I though this point was pretty straight forward. If you have a massive WAN with tons of datacenters and loads of compute workload that needs cross DC mobility you probably also have people smart enough (or the money to get them) to come up with a good architecture that solves the problem in a reasonable way. The more important point which you seem to have missed is that cross DC IP mobility is probably what people have been trying to achieve and that is likely the problem. If you stop trying to able to shift IPs anywhere you want and embrace the fact that workloads are dynamic and IPs will come and go then suddenly things are a whole lot easier, more scalable and more resilient.
If anything you agree with my point by confirming billions of dollars of transactions are involved.

I am not tanked up on any cloud "kool-aid", I have just refused to subscribe to enterprise architectures that have never made sense and never will. If you actually follow evolution of systems I think my argument is even more compelling, not less.

They don't need to. Their large HDS, EMC or other overpriced SAN is a completely reasonable replacement for S3 or Ceph, I just used those as examples.

Indeed they are, that is why it's so important that the network plane is open. So that tooling can be built or integrated that provides all of those things. While it's not then you are constantly hitting up against the age old vendor argument of "That feature is not currently implemented" or "We don't expose those counters" or "We realise this violates the spec but we can't make a breaking change to fix it".

As for regulators, I am yet to meet one that could even follow this conversation. Maybe your experience has been better but I wouldn't say "regulator friendly" is a good thing on the balance of probabilities.

As for your other comments about how much money is spent on these sorts of platforms vs existing enterprise and carrier datacenters I completely agree, it is tiny.

However what I disagree with is that is a meaningful metric. The trends are pretty clear, computing is becoming commoditised to the point that it's not going to make sense to do it in-house any more. When that time comes it's not those old and crufty enterprise models that are going to be left standing.