I’ve considered not responding to this separate reply, because it feels like a very subjective perception and it’s hard arguing with perceptions.
But since we talked psychology earlier, I think a similar approach here is permissible as well, and I’ll share my perception in return. Because your perception makes sense from your perspective, but it’s flawed on more then one level from my end.
#1
Before looking into it more because images were missing, I’ve came across and read Moving images from Imgur to Panoramax. Based on just that, I would’ve belonged to the “thank you, great job!”-group and no more. And here’s why.
Without clicking trough to the linked GitHub issue (which according to Discourse only 4 people did, including me just now), it sounds like you’re only moving the images from one host to another and replacing the URL accordingly, without removing the image-key.
I know of Panoramax, seen it, but never realised that this wasn’t just about moving them, but also a different implementation all together. Basically removing the image-tag (with its clickable link to an actual image) and replacing this with the panoramax-tag which contains a hash which currently isn’t clickable yet, and isn’t yet supported by the majority of data consumers/editors.
I’m pretty sure that if the title was “Deleting 30k+ image-links and replacing them with Panoramax-hashes” you would’ve been met with a lot more resistance - it could be an interesting experiment to still do that. 
It could even be argued that this announcement was misleading in those respects. Now to be clear, I don’t want to assume negative intentions here nor accuse you of same, but even looking at it as positive as possible, it did falsely assume everyone knows what Panoramax is - and how using Panoramax would significantly differ from using imgur.
That basically it was a announcement (because in fairness, it doesn’t even read as a proposal) enhances this notion: deleting 30k+ tags surely would justify a proposal/discussion (see #2 below), rather then an announcement, right?
I’m surpressing the urge to insert some applicable memes in here, but I’m not sure it would be appreciated as intended.
#2
Moving images from Imgur to Panoramax is also the closest we came to “discussing the mass/mechanical edit”. But wasn’t properly labelled or written as such, didn’t cover fully what what the change entails, and in general doesn’t meat the requirements as put down by the Automated Edits code of conduct.
On a side note, the code of conduct has both arguments against and in favour of how you proceeded, but the key here is: it should’ve been discussed beforehand (clearly, with all implications clearly put out there, not hidden behind a link).
#3 / In conclusion
Because it was “announced” and not “proposed”, did not clearly explain what the actual impact was, I think it’s also fair to assume that the people who’ll be reaching out are:
- Either people who know you, were already involved and/or in the know, and therefore to be considered similarly subjective to the approach, or…
- Didn’t grasp the scope of the change, just considered it replacing one host (URL) for another, and a commercial one for something open source at that, “so sure, thumbs up!”. Or: "imgur bad, panoramax good”, as @lipuma nicely put it.
Hence, generally positive. 
Having said all that, I’d be in favour of restoring the image-tags as proposed by @draconic_mapper, until such a time that discussion has taken place and community consent has actually been asked - and subsequently given. Opt-in, and not opt-out, if you will.